From 41741f32fcf088e93f746a82549392ec5fd82e5f Mon Sep 17 00:00:00 2001 From: Uladzimir Havenchyk Date: Thu, 6 Dec 2018 23:01:48 +0300 Subject: [PATCH] Remove gitter links --- CONTRIBUTING.md | 14 +- README-zh_CN.md | 63 +- README.md | 2581 +++++++++++++++++++++++------------------------ 3 files changed, 1326 insertions(+), 1332 deletions(-) diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md index 36386a4d2..031cda990 100644 --- a/CONTRIBUTING.md +++ b/CONTRIBUTING.md @@ -1,6 +1,6 @@ # Contributing to TypeORM -We would love for you to contribute to TypeORM and help make it even better than it is today! +We would love for you to contribute to TypeORM and help make it even better than it is today! As a contributor, here are the guidelines we would like you to follow: - [Question or Problem?](#question) @@ -13,21 +13,21 @@ As a contributor, here are the guidelines we would like you to follow: There are several ways how you can ask your question: * You can create a question on [StackOverflow](https://stackoverflow.com/questions/tagged/typeorm) where the questions should be tagged with tag `typeorm`. +* You can ask on [Slack](https://join.slack.com/t/typeorm/shared_invite/enQtNDQ1MzA3MDA5MTExLTFiNDEyOGUxZGQyYWIwOTA0NDQxODdkOGQ0OTUxNzFjYjUwY2E0ZmFlODc5OTYyYzAzNGM3MGZjYzhjYTBiZTY) * You can create issue on [github](https://github.com/typeorm/typeorm/issues) -* You can write your questions in our [gitter channel](https://gitter.im/typeorm/typeorm) * If you have a Skype then try to find me there (`Umed Khudoiberdiev`) Preferred way if you create your question on StackOverflow, or create a github issue. ## Found a security vulnerability? -If you find a security vulnerability or something that should be discussed personally, +If you find a security vulnerability or something that should be discussed personally, please contact me within my [email](https://github.com/typeorm/typeorm/blob/master/package.json#L10). ## Found a Bug? -If you find a bug in the source code, you can help us by [submitting an issue](#submit-issue) to our -[GitHub Repository](https://github.com/typeorm/typeorm). +If you find a bug in the source code, you can help us by [submitting an issue](#submit-issue) to our +[GitHub Repository](https://github.com/typeorm/typeorm). Even better, you can [submit a Pull Request](#submit-pr) with a fix. ## Missing a Feature? @@ -46,11 +46,11 @@ and help you to craft the change so that it is successfully accepted into the pr ### Submitting an Issue -Before you submit an issue, please search the issue tracker, +Before you submit an issue, please search the issue tracker, maybe an issue for your problem already exists and the discussion might inform you of workarounds readily available. We want to fix all the issues as soon as possible, but before fixing a bug we need to reproduce and confirm it. - In order to reproduce bugs we ask you to provide a minimal code snippet that shows a reproduction of the problem. + In order to reproduce bugs we ask you to provide a minimal code snippet that shows a reproduction of the problem. You can file new issues by filling out our [new issue form](https://github.com/typeorm/typeorm/issues/new). diff --git a/README-zh_CN.md b/README-zh_CN.md index 844c5aea4..3e143a924 100644 --- a/README-zh_CN.md +++ b/README-zh_CN.md @@ -13,9 +13,6 @@ - - -

@@ -147,7 +144,7 @@ await timber.remove(); ## 请注意 -这个文档可能不是最新的。 +这个文档可能不是最新的。 可以去[官网](http://typeorm.io)查看最新的英文文档。 非常欢迎你的贡献。 @@ -163,7 +160,7 @@ await timber.remove(); 在应用里全局引用一下: - * 比如在app.ts的入口处 `require("reflect-metadata")` + * 比如在app.ts的入口处 `require("reflect-metadata")` 3. 你可能需要安装node类型： @@ -172,31 +169,31 @@ await timber.remove(); 4. 安装数据库驱动: * **MySQL** 或 **MariaDB** - + `npm install mysql --save` - + * **PostgreSQL** - + `npm install pg --save` - + * **SQLite** - + `npm install sqlite3 --save` - + * **Microsoft SQL Server** - + `npm install mssql --save` * **sql.js** `npm install sql.js --save` - + * **Oracle** (experimental) - + `npm install oracledb --save` - + 可以根据你的数据库选择安装上面的任意一个. - + 使用oracle驱动需要参考安装说明：[地址](https://github.com/oracle/node-oracledb). #### TypeScript配置 @@ -507,7 +504,7 @@ createConnection({ synchronize: true, logging: false }).then(connection => { - // 这里可以写实体操作相关的代码 + // 这里可以写实体操作相关的代码 }).catch(error => console.log(error)); ``` @@ -516,7 +513,7 @@ createConnection({ 把Photo实体加到数据连接的实体列表中，所有需要在这个连接下使用的实体都必须加到这个列表中。 -`synchronize`选项可以在应用启动时确保你的实体和数据库保持同步。 +`synchronize`选项可以在应用启动时确保你的实体和数据库保持同步。 ### 引用目录下的所有实体 @@ -585,7 +582,7 @@ createConnection(/*...*/).then(connection => { }).catch(error => console.log(error)); ``` - + ### 使用async/await语法 现在利用TypeScript的async/await语法来实现同样的功能： @@ -656,7 +653,7 @@ createConnection(/*...*/).then(async connection => { }).catch(error => console.log(error)); ``` - + ### 从数据库中取photos 现在来尝试用Repository做一些取数据方面的操作: @@ -726,7 +723,7 @@ createConnection(/*...*/).then(async connection => { await photoRepository.remove(photoToRemove); }).catch(error => console.log(error)); -``` +``` 这个`id = 1`的photo就在数据库中被移除了。 @@ -832,10 +829,10 @@ createConnection(/*...*/).then(async connection => { }).catch(error => console.log(error)); ``` - + ### 双向关系 -关系可以是单向的或是双向的. +关系可以是单向的或是双向的. 现在PhotoMetadata和Photo的关系是单向的，关系拥有者是PhotoMetadata，Photo并不知道PhotoMetadata，这样如果要想从Photo里得到PhotoMetadata的数据会比较麻烦。 现在来改变一下，把单向改成双向： @@ -852,7 +849,7 @@ export class PhotoMetadata { @JoinColumn() photo: Photo; } -``` +``` ```typescript import {Entity, Column, PrimaryGeneratedColumn, OneToOne} from "typeorm"; @@ -866,7 +863,7 @@ export class Photo { @OneToOne(type => PhotoMetadata, photoMetadata => photoMetadata.photo) metadata: PhotoMetadata; } -``` +``` `photo => photo.metadata` 是用来指定反向关系的字段名字，photo.metadata就指出了Photo里的metadata字段名字。 当然也可以使用`@OneToOne('metadata')`来达到同样的目的，不过这种对于以后的代码重构不友好。 @@ -897,8 +894,8 @@ createConnection(/*...*/).then(async connection => { `alias` 是FindOptions的一个必需选项，这是你自己在select里定义的别名，然后需要用在接下来的 where, order by, group by, join 以及其他表达式. -这里还用到了`innerJoinAndSelect`，表示内联查询photo.metadata的数据。 -`"photo.metadata"`里"photo"是一个别名，"metadata"则是你想查询的那个对象的属性名。 +这里还用到了`innerJoinAndSelect`，表示内联查询photo.metadata的数据。 +`"photo.metadata"`里"photo"是一个别名，"metadata"则是你想查询的那个对象的属性名。 `"metadata"`: 是内联返回数据的新的别名. 下面来尝试第二种方式：`QueryBuilder`来达到同样的目的. 使用`QueryBuilder`可以优雅完成复杂的查询: @@ -958,7 +955,7 @@ createConnection(options).then(async connection => { metadata.compressed = true; metadata.comment = "cybershoot"; metadata.orientation = "portait"; - + photo.metadata = metadata; // 连接起来 // 得到repository @@ -970,7 +967,7 @@ createConnection(options).then(async connection => { console.log("Photo is saved, photo metadata is saved too.") }).catch(error => console.log(error)); -``` +``` ### 多对一/一对多关系 @@ -1044,11 +1041,11 @@ export class Photo { | authorId | int(11) | FOREIGN KEY | +-------------+--------------+----------------------------+ ``` - + ### 多对多关系 假设photo可以存在多个相册中，并且相册里可以包含多个photo。 -先创建一个`Album`类 +先创建一个`Album`类 ```typescript import {Entity, PrimaryGeneratedColumn, Column, ManyToMany, JoinTable} from "typeorm"; @@ -1067,7 +1064,7 @@ export class Album { photos: Photo[]; } ``` - + `@JoinTable`多对多关系拥有者必须指定的。 接着给`Photo`实体加个反向关系: @@ -1101,7 +1098,7 @@ const options: ConnectionOptions = { }; ``` -现在来往数据库里插入albums和photos +现在来往数据库里插入albums和photos ```typescript let connection = await createConnection(options); diff --git a/README.md b/README.md index 41f0819a6..fa50a94ec 100644 --- a/README.md +++ b/README.md @@ -1,1292 +1,1289 @@ -
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- -TypeORM is an [ORM](https://en.wikipedia.org/wiki/Object-relational_mapping) -that can run in NodeJS, Browser, Cordova, PhoneGap, Ionic, React Native, NativeScript, Expo, and Electron platforms -and can be used with TypeScript and JavaScript (ES5, ES6, ES7, ES8). -Its goal is to always support the latest JavaScript features and provide additional features -that help you to develop any kind of application that uses databases - from -small applications with a few tables to large scale enterprise applications -with multiple databases. - -TypeORM supports both Active Record and Data Mapper patterns, -unlike all other JavaScript ORMs currently in existence, -which means you can write high quality, loosely coupled, scalable, -maintainable applications the most productive way. - -TypeORM is highly influenced by other ORMs, such as [Hibernate](http://hibernate.org/orm/), - [Doctrine](http://www.doctrine-project.org/) and [Entity Framework](https://www.asp.net/entity-framework). - -Some TypeORM features: - -* supports both DataMapper and ActiveRecord (your choice) -* entities and columns -* database-specific column types -* entity manager -* repositories and custom repositories -* clean object relational model -* associations (relations) -* eager and lazy relations -* uni-directional, bi-directional and self-referenced relations -* supports multiple inheritance patterns -* cascades -* indices -* transactions -* migrations and automatic migrations generation -* connection pooling -* replication -* using multiple database connections -* working with multiple databases types -* cross-database and cross-schema queries -* elegant-syntax, flexible and powerful QueryBuilder -* left and inner joins -* proper pagination for queries using joins -* query caching -* streaming raw results -* logging -* listeners and subscribers (hooks) -* supports closure table pattern -* schema declaration in models or separate configuration files -* connection configuration in json / xml / yml / env formats -* supports MySQL / MariaDB / Postgres / SQLite / Microsoft SQL Server / Oracle / sql.js -* supports MongoDB NoSQL database -* works in NodeJS / Browser / Ionic / Cordova / React Native / NativeScript / Expo / Electron platforms -* TypeScript and JavaScript support -* produced code is performant, flexible, clean and maintainable -* follows all possible best practices -* CLI - -And more... - -With TypeORM your models look like this: - -```typescript -import {Entity, PrimaryGeneratedColumn, Column} from "typeorm"; - -@Entity() -export class User { - - @PrimaryGeneratedColumn() - id: number; - - @Column() - firstName: string; - - @Column() - lastName: string; - - @Column() - age: number; - -} -``` - -And your domain logic looks like this: - -```typescript -const user = new User(); -user.firstName = "Timber"; -user.lastName = "Saw"; -user.age = 25; -await repository.save(user); - -const allUsers = await repository.find(); -const firstUser = await repository.findOne(1); // find by id -const timber = await repository.findOne({ firstName: "Timber", lastName: "Saw" }); - -await repository.remove(timber); -``` - -Alternatively, if you prefer to use the `ActiveRecord` implementation, you can use it as well: - -```typescript -import {Entity, PrimaryGeneratedColumn, Column, BaseEntity} from "typeorm"; - -@Entity() -export class User extends BaseEntity { - - @PrimaryGeneratedColumn() - id: number; - - @Column() - firstName: string; - - @Column() - lastName: string; - - @Column() - age: number; - -} -``` - -And your domain logic will look this way: - -```typescript -const user = new User(); -user.firstName = "Timber"; -user.lastName = "Saw"; -user.age = 25; -await user.save(); - -const allUsers = await User.find(); -const firstUser = await User.findOne(1); -const timber = await User.findOne({ firstName: "Timber", lastName: "Saw" }); - -await timber.remove(); -``` - -## Installation - - -1. Install the npm package: - - `npm install typeorm --save` - -2. You need to install `reflect-metadata` shim: - - `npm install reflect-metadata --save` - - and import it somewhere in the global place of your app (for example in `app.ts`): - - `import "reflect-metadata";` - -3. You may need to install node typings: - - `npm install @types/node --save` - -4. Install a database driver: - - * for **MySQL** or **MariaDB** - - `npm install mysql --save` (you can install `mysql2` instead as well) - - * for **PostgreSQL** - - `npm install pg --save` - - * for **SQLite** - - `npm install sqlite3 --save` - - * for **Microsoft SQL Server** - - `npm install mssql --save` - - * for **sql.js** - - `npm install sql.js --save` - - * for **Oracle** - - `npm install oracledb --save` - - Install only *one* of them, depending on which database you use. - - To make the Oracle driver work, you need to follow the installation instructions from - [their](https://github.com/oracle/node-oracledb) site. - - * for **MongoDB** (experimental) - - `npm install mongodb --save` - - * for **NativeScript**, **react-native** and **Cordova** - - Check [documentation of supported platforms](docs/supported-platforms.md) - - - -##### TypeScript configuration - -Also, make sure you are using TypeScript compiler version **2.3** or greater, -and you have enabled the following settings in `tsconfig.json`: - -```json -"emitDecoratorMetadata": true, -"experimentalDecorators": true, -``` - -You may also need to enable `es6` in the `lib` section of compiler options, or install `es6-shim` from `@types`. - -## Quick Start - -The quickest way to get started with TypeORM is to use its CLI commands to generate a starter project. -Quick start works only if you are using TypeORM in a NodeJS application. -If you are using other platforms, proceed to the [step-by-step guide](#step-by-step-guide). - -First, install TypeORM globally: - -``` -npm install typeorm -g -``` - -Then go to the directory where you want to create a new project and run the command: - -``` -typeorm init --name MyProject --database mysql -``` - -Where `name` is the name of your project and `database` is the database you'll use. -Database can be one of the following values: `mysql`, `mariadb`, `postgres`, `sqlite`, `mssql`, `oracle`, `mongodb`, -`cordova`, `react-native`, `expo`, `nativescript`. - -This command will generate a new project in the `MyProject` directory with the following files: - -``` -MyProject -├── src // place of your TypeScript code -│ ├── entity // place where your entities (database models) are stored -│ │ └── User.ts // sample entity -│ ├── migration // place where your migrations are stored -│ └── index.ts // start point of your application -├── .gitignore // standard gitignore file -├── ormconfig.json // ORM and database connection configuration -├── package.json // node module dependencies -├── README.md // simple readme file -└── tsconfig.json // TypeScript compiler options -``` - -> You can also run `typeorm init` on an existing node project, but be careful - it may override some files you already have. - -The next step is to install new project dependencies: - -``` -cd MyProject -npm install -``` - -While installation is in progress, edit the `ormconfig.json` file and put your own database connection configuration options in there: - -```json -{ - "type": "mysql", - "host": "localhost", - "port": 3306, - "username": "test", - "password": "test", - "database": "test", - "synchronize": true, - "logging": false, - "entities": [ - "src/entity/**/*.ts" - ], - "migrations": [ - "src/migration/**/*.ts" - ], - "subscribers": [ - "src/subscriber/**/*.ts" - ] -} -``` - -Particularly, most of the time you'll only need to configure -`host`, `username`, `password`, `database` and maybe `port` options. - -Once you finish with configuration and all node modules are installed, you can run your application: - -``` -npm start -``` - -That's it, your application should successfully run and insert a new user into the database. -You can continue to work with this project and integrate other modules you need and start -creating more entities. - -> You can generate an even more advanced project with express installed by running -`typeorm init --name MyProject --database mysql --express` command. - -## Step-by-Step Guide - -What are you expecting from ORM? -First of all, you are expecting it will create database tables for you -and find / insert / update / delete your data without the pain of -having to write lots of hardly maintainable SQL queries. -This guide will show you how to setup TypeORM from scratch and make it do what you are expecting from an ORM. - -### Create a model - -Working with a database starts from creating tables. -How do you tell TypeORM to create a database table? -The answer is - through the models. -Your models in your app are your database tables. - -For example, you have a `Photo` model: - -```typescript -export class Photo { - id: number; - name: string; - description: string; - filename: string; - views: number; -} -``` - -And you want to store photos in your database. -To store things in the database, first you need a database table, -and database tables are created from your models. -Not all models, but only those you define as *entities*. - -### Create an entity - -*Entity* is your model decorated by an `@Entity` decorator. -A database table will be created for such models. -You work with entities everywhere with TypeORM. -You can load/insert/update/remove and perform other operations with them. - -Let's make our `Photo` model as an entity: - -```typescript -import {Entity} from "typeorm"; - -@Entity() -export class Photo { - id: number; - name: string; - description: string; - filename: string; - views: number; - isPublished: boolean; -} -``` - -Now, a database table will be created for the `Photo` entity and we'll be able to work with it anywhere in our app. -We have created a database table, however what table can exist without columns? -Let's create a few columns in our database table. - -### Adding table columns - -To add database columns, you simply need to decorate an entity's properties you want to make into a column -with a `@Column` decorator. - -```typescript -import {Entity, Column} from "typeorm"; - -@Entity() -export class Photo { - - @Column() - id: number; - - @Column() - name: string; - - @Column() - description: string; - - @Column() - filename: string; - - @Column() - views: number; - - @Column() - isPublished: boolean; -} -``` - -Now `id`, `name`, `description`, `filename`, `views` and `isPublished` columns will be added to the `photo` table. -Column types in the database are inferred from the property types you used, e.g. -`number` will be converted into `integer`, `string` into `varchar`, `boolean` into `bool`, etc. -But you can use any column type your database supports by implicitly specifying a column type into the `@Column` decorator. - -We generated a database table with columns, but there is one thing left. -Each database table must have a column with a primary key. - -### Creating a primary column - -Each entity **must** have at least one primary key column. -This is a requirement and you can't avoid it. -To make a column a primary key, you need to use `@PrimaryColumn` decorator. - -```typescript -import {Entity, Column, PrimaryColumn} from "typeorm"; - -@Entity() -export class Photo { - - @PrimaryColumn() - id: number; - - @Column() - name: string; - - @Column() - description: string; - - @Column() - filename: string; - - @Column() - views: number; - - @Column() - isPublished: boolean; -} -``` - -### Creating an auto generated column - -Now, let's say you want your id column to be auto-generated (this is known as auto-increment / sequence / serial / generated identity column). -To do that, you need to change the `@PrimaryColumn` decorator to a `@PrimaryGeneratedColumn` decorator: - -```typescript -import {Entity, Column, PrimaryGeneratedColumn} from "typeorm"; - -@Entity() -export class Photo { - - @PrimaryGeneratedColumn() - id: number; - - @Column() - name: string; - - @Column() - description: string; - - @Column() - filename: string; - - @Column() - views: number; - - @Column() - isPublished: boolean; -} -``` - -### Column data types - -Next, let's fix our data types. By default, string is mapped to a varchar(255)-like type (depending on the database type). -Number is mapped to a integer-like type (depending on the database type). -We don't want all our columns to be limited varchars or integers. -Let's setup correct data types: - -```typescript -import {Entity, Column, PrimaryGeneratedColumn} from "typeorm"; - -@Entity() -export class Photo { - - @PrimaryGeneratedColumn() - id: number; - - @Column({ - length: 100 - }) - name: string; - - @Column("text") - description: string; - - @Column() - filename: string; - - @Column("double") - views: number; - - @Column() - isPublished: boolean; -} -``` - -Column types are database-specific. -You can set any column type your database supports. -More information on supported column types can be found [here](./docs/entities.md#column-types). - -### Creating a connection to the database - -Now, when our entity is created, let's create an `index.ts` (or `app.ts` whatever you call it) file and set up our connection there: - -```typescript -import "reflect-metadata"; -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; - -createConnection({ - type: "mysql", - host: "localhost", - port: 3306, - username: "root", - password: "admin", - database: "test", - entities: [ - Photo - ], - synchronize: true, - logging: false -}).then(connection => { - // here you can start to work with your entities -}).catch(error => console.log(error)); -``` - -We are using MySQL in this example, but you can use any other supported database. -To use another database, simply change the `type` in the options to the database type you are using: -mysql, mariadb, postgres, sqlite, mssql, oracle, cordova, nativescript, react-native, expo, or mongodb. -Also make sure to use your own host, port, username, password and database settings. - -We added our Photo entity to the list of entities for this connection. -Each entity you are using in your connection must be listed there. - -Setting `synchronize` makes sure your entities will be synced with the database, every time you run the application. - -### Loading all entities from the directory - -Later, when we create more entities we need to add them to the entities in our configuration. -This is not very convenient, so instead we can set up the whole directory, from where all entities will be connected and used in our connection: - -```typescript -import {createConnection} from "typeorm"; - -createConnection({ - type: "mysql", - host: "localhost", - port: 3306, - username: "root", - password: "admin", - database: "test", - entities: [ - __dirname + "/entity/*.js" - ], - synchronize: true, -}).then(connection => { - // here you can start to work with your entities -}).catch(error => console.log(error)); -``` - -But be careful with this approach. -If you are using `ts-node` then you need to specify paths to `.ts` files instead. -If you are using `outDir` then you'll need to specify paths to `.js` files inside outDir directory. -If you are using `outDir` and when you remove or rename your entities make sure to clear `outDir` directory -and re-compile your project again, because when you remove your source `.ts` files their compiled `.js` versions -aren't removed from output directory and still are loaded by TypeORM because they are present in the `outDir` directory. - -### Running the application - -Now if you run your `index.ts`, a connection with database will be initialized and a database table for your photos will be created. - - -```shell -+-------------+--------------+----------------------------+ -| photo | -+-------------+--------------+----------------------------+ -| id | int(11) | PRIMARY KEY AUTO_INCREMENT | -| name | varchar(500) | | -| description | text | | -| filename | varchar(255) | | -| views | int(11) | | -| isPublished | boolean | | -+-------------+--------------+----------------------------+ -``` - -### Creating and inserting a photo into the database - -Now let's create a new photo to save it in the database: - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; - -createConnection(/*...*/).then(connection => { - - let photo = new Photo(); - photo.name = "Me and Bears"; - photo.description = "I am near polar bears"; - photo.filename = "photo-with-bears.jpg"; - photo.views = 1; - photo.isPublished = true; - -    return connection.manager - .save(photo) - .then(photo => { - console.log("Photo has been saved. Photo id is", photo.id); - }); - -}).catch(error => console.log(error)); -``` - -Once your entity is saved it will get a newly generated id. -`save` method returns an instance of the same object you pass to it. -It's not a new copy of the object, it modifies its "id" and returns it. - -### Using async/await syntax - -Let's take advantage of the latest ES8 (ES2017) features and use async/await syntax instead: - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; - -createConnection(/*...*/).then(async connection => { - - let photo = new Photo(); - photo.name = "Me and Bears"; - photo.description = "I am near polar bears"; - photo.filename = "photo-with-bears.jpg"; - photo.views = 1; - photo.isPublished = true; - - await connection.manager.save(photo); - console.log("Photo has been saved"); - -}).catch(error => console.log(error)); -``` - -### Using Entity Manager - -We just created a new photo and saved it in the database. -We used `EntityManager` to save it. -Using entity manager you can manipulate any entity in your app. -For example, let's load our saved entity: - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; - -createConnection(/*...*/).then(async connection => { - - /*...*/ - let savedPhotos = await connection.manager.find(Photo); - console.log("All photos from the db: ", savedPhotos); - -}).catch(error => console.log(error)); -``` - -`savedPhotos` will be an array of Photo objects with the data loaded from the database. - -Learn more about EntityManager [here](./docs/working-with-entity-manager.md). - -### Using Repositories - -Now let's refactor our code and use `Repository` instead of `EntityManager`. -Each entity has its own repository which handles all operations with its entity. -When you deal with entities a lot, Repositories are more convenient to use than EntityManagers: - - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; - -createConnection(/*...*/).then(async connection => { - - let photo = new Photo(); - photo.name = "Me and Bears"; - photo.description = "I am near polar bears"; - photo.filename = "photo-with-bears.jpg"; - photo.views = 1; - photo.isPublished = true; - - let photoRepository = connection.getRepository(Photo); - - await photoRepository.save(photo); - console.log("Photo has been saved"); - - let savedPhotos = await photoRepository.find(); - console.log("All photos from the db: ", savedPhotos); - -}).catch(error => console.log(error)); -``` - -Learn more about Repository [here](./docs/working-with-repository.md). - -### Loading from the database - -Let's try more load operations using the Repository: - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; - -createConnection(/*...*/).then(async connection => { - - /*...*/ - let allPhotos = await photoRepository.find(); - console.log("All photos from the db: ", allPhotos); - - let firstPhoto = await photoRepository.findOne(1); - console.log("First photo from the db: ", firstPhoto); - - let meAndBearsPhoto = await photoRepository.findOne({ name: "Me and Bears" }); - console.log("Me and Bears photo from the db: ", meAndBearsPhoto); - - let allViewedPhotos = await photoRepository.find({ views: 1 }); - console.log("All viewed photos: ", allViewedPhotos); - - let allPublishedPhotos = await photoRepository.find({ isPublished: true }); - console.log("All published photos: ", allPublishedPhotos); - - let [allPhotos, photosCount] = await photoRepository.findAndCount(); - console.log("All photos: ", allPhotos); - console.log("Photos count: ", photosCount); - -}).catch(error => console.log(error)); -``` - -### Updating in the database - -Now let's load a single photo from the database, update it and save it: - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; - -createConnection(/*...*/).then(async connection => { - - /*...*/ - let photoToUpdate = await photoRepository.findOne(1); - photoToUpdate.name = "Me, my friends and polar bears"; - await photoRepository.save(photoToUpdate); - -}).catch(error => console.log(error)); -``` - -Now photo with `id = 1` will be updated in the database. - -### Removing from the database - -Now let's remove our photo from the database: - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; - -createConnection(/*...*/).then(async connection => { - - /*...*/ - let photoToRemove = await photoRepository.findOne(1); - await photoRepository.remove(photoToRemove); - -}).catch(error => console.log(error)); -``` - -Now photo with `id = 1` will be removed from the database. - -### Creating a one-to-one relation - -Let's create a one-to-one relation with another class. -Let's create a new class in `PhotoMetadata.ts`. This PhotoMetadata class is supposed to contain our photo's additional meta-information: - -```typescript -import {Entity, Column, PrimaryGeneratedColumn, OneToOne, JoinColumn} from "typeorm"; -import {Photo} from "./Photo"; - -@Entity() -export class PhotoMetadata { - - @PrimaryGeneratedColumn() - id: number; - - @Column("int") - height: number; - - @Column("int") - width: number; - - @Column() - orientation: string; - - @Column() - compressed: boolean; - - @Column() - comment: string; - - @OneToOne(type => Photo) - @JoinColumn() - photo: Photo; -} -``` - -Here, we are using a new decorator called `@OneToOne`. It allows us to create a one-to-one relationship between two entities. -`type => Photo` is a function that returns the class of the entity with which we want to make our relationship. -We are forced to use a function that returns a class, instead of using the class directly, because of the language specifics. -We can also write it as `() => Photo`, but we use `type => Photo` as a convention to increase code readability. -The type variable itself does not contain anything. - -We also add a `@JoinColumn` decorator, which indicates that this side of the relationship will own the relationship. -Relations can be unidirectional or bidirectional. -Only one side of relational can be owning. -Using `@JoinColumn` decorator is required on the owner side of the relationship. - -If you run the app, you'll see a newly generated table, and it will contain a column with a foreign key for the photo relation: - -```shell -+-------------+--------------+----------------------------+ -| photo_metadata | -+-------------+--------------+----------------------------+ -| id | int(11) | PRIMARY KEY AUTO_INCREMENT | -| height | int(11) | | -| width | int(11) | | -| comment | varchar(255) | | -| compressed | boolean | | -| orientation | varchar(255) | | -| photoId | int(11) | FOREIGN KEY | -+-------------+--------------+----------------------------+ -``` - -### Save a one-to-one relation - -Now let's save a photo, its metadata and attach them to each other. - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; -import {PhotoMetadata} from "./entity/PhotoMetadata"; - -createConnection(/*...*/).then(async connection => { - - // create a photo - let photo = new Photo(); - photo.name = "Me and Bears"; - photo.description = "I am near polar bears"; - photo.filename = "photo-with-bears.jpg"; - photo.isPublished = true; - - // create a photo metadata - let metadata = new PhotoMetadata(); - metadata.height = 640; - metadata.width = 480; - metadata.compressed = true; - metadata.comment = "cybershoot"; - metadata.orientation = "portait"; - metadata.photo = photo; // this way we connect them - - // get entity repositories - let photoRepository = connection.getRepository(Photo); - let metadataRepository = connection.getRepository(PhotoMetadata); - - // first we should save a photo - await photoRepository.save(photo); - - // photo is saved. Now we need to save a photo metadata - await metadataRepository.save(metadata); - - // done - console.log("Metadata is saved, and relation between metadata and photo is created in the database too"); - -}).catch(error => console.log(error)); -``` - -### Inverse side of the relationship - -Relations can be unidirectional or bidirectional. -Currently, our relation between PhotoMetadata and Photo is unidirectional. -The owner of the relation is PhotoMetadata, and Photo doesn't know anything about PhotoMetadata. -This makes it complicated to access PhotoMetadata from the Photo side. -To fix this issue we should add an inverse relation, and make relations between PhotoMetadata and Photo bidirectional. -Let's modify our entities: - -```typescript -import {Entity, Column, PrimaryGeneratedColumn, OneToOne, JoinColumn} from "typeorm"; -import {Photo} from "./Photo"; - -@Entity() -export class PhotoMetadata { - - /* ... other columns */ - - @OneToOne(type => Photo, photo => photo.metadata) - @JoinColumn() - photo: Photo; -} -``` - -```typescript -import {Entity, Column, PrimaryGeneratedColumn, OneToOne} from "typeorm"; -import {PhotoMetadata} from "./PhotoMetadata"; - -@Entity() -export class Photo { - - /* ... other columns */ - - @OneToOne(type => PhotoMetadata, photoMetadata => photoMetadata.photo) - metadata: PhotoMetadata; -} -``` - -`photo => photo.metadata` is a function that returns the name of the inverse side of the relation. -Here we show that the metadata property of the Photo class is where we store PhotoMetadata in the Photo class. -Instead of passing a function that returns a property of the photo, you could alternatively simply pass a string to `@OneToOne` decorator, like `"metadata"`. -But we used this function-typed approach to make our refactoring easier. - -Note that we should use `@JoinColumn` decorator only on one side of a relation. -Whichever side you put this decorator on will be the owning side of the relationship. -The owning side of a relationship contains a column with a foreign key in the database. - -### Loading objects with their relations - -Now let's load our photo and its photo metadata in a single query. -There are two ways to do it - using `find*` methods or using `QueryBuilder` functionality. -Let's use `find*` methods first. -`find*` methods allow you to specify an object with the `FindOneOptions` / `FindManyOptions` interface. - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; -import {PhotoMetadata} from "./entity/PhotoMetadata"; - -createConnection(/*...*/).then(async connection => { - - /*...*/ - let photoRepository = connection.getRepository(Photo); - let photos = await photoRepository.find({ relations: ["metadata"] }); - -}).catch(error => console.log(error)); -``` - -Here, photos will contain an array of photos from the database, and each photo will contain its photo metadata. -Learn more about Find Options in [this documentation](./docs/find-options.md). - -Using find options is good and dead simple, but if you need a more complex query, you should use `QueryBuilder` instead. -`QueryBuilder` allows more complex queries to be used in an elegant way: - -```typescript -import {createConnection} from "typeorm"; -import {Photo} from "./entity/Photo"; -import {PhotoMetadata} from "./entity/PhotoMetadata"; - -createConnection(/*...*/).then(async connection => { - - /*...*/ - let photos = await connection - .getRepository(Photo) - .createQueryBuilder("photo") - .innerJoinAndSelect("photo.metadata", "metadata") - .getMany(); - - -}).catch(error => console.log(error)); -``` - -`QueryBuilder` allows creation and execution of SQL queries of almost any complexity. -When you work with `QueryBuilder`, think like you are creating an SQL query. -In this example, "photo" and "metadata" are aliases applied to selected photos. -You use aliases to access columns and properties of the selected data. - -### Using cascades to automatically save related objects - -We can setup cascade options in our relations, in the cases when we want our related object to be saved whenever the other object is saved. -Let's change our photo's `@OneToOne` decorator a bit: - -```typescript -export class Photo { - /// ... other columns - - @OneToOne(type => PhotoMetadata, metadata => metadata.photo, { - cascade: true, - }) - metadata: PhotoMetadata; -} -``` - -Using `cascade` allows us not to separately save photo and separately save metadata objects now. -Now we can simply save a photo object, and the metadata object will be saved automatically because of cascade options. - -```typescript -createConnection(options).then(async connection => { - - // create photo object - let photo = new Photo(); - photo.name = "Me and Bears"; - photo.description = "I am near polar bears"; - photo.filename = "photo-with-bears.jpg"; - photo.isPublished = true; - - // create photo metadata object - let metadata = new PhotoMetadata(); - metadata.height = 640; - metadata.width = 480; - metadata.compressed = true; - metadata.comment = "cybershoot"; - metadata.orientation = "portait"; - - photo.metadata = metadata; // this way we connect them - - // get repository - let photoRepository = connection.getRepository(Photo); - - // saving a photo also save the metadata - await photoRepository.save(photo); - - console.log("Photo is saved, photo metadata is saved too.") - -}).catch(error => console.log(error)); -``` - -### Creating a many-to-one / one-to-many relation - -Let's create a many-to-one / one-to-many relation. -Let's say a photo has one author, and each author can have many photos. -First, let's create an `Author` class: - -```typescript -import {Entity, Column, PrimaryGeneratedColumn, OneToMany, JoinColumn} from "typeorm"; -import {Photo} from "./Photo"; - -@Entity() -export class Author { - - @PrimaryGeneratedColumn() - id: number; - - @Column() - name: string; - - @OneToMany(type => Photo, photo => photo.author) // note: we will create author property in the Photo class below - photos: Photo[]; -} -``` - -`Author` contains an inverse side of a relation. -`OneToMany` is always an inverse side of relation, and it can't exist without `ManyToOne` on the other side of the relation. - -Now let's add the owner side of the relation into the Photo entity: - -```typescript -import {Entity, Column, PrimaryGeneratedColumn, ManyToOne} from "typeorm"; -import {PhotoMetadata} from "./PhotoMetadata"; -import {Author} from "./Author"; - -@Entity() -export class Photo { - - /* ... other columns */ - - @ManyToOne(type => Author, author => author.photos) - author: Author; -} -``` - -In many-to-one / one-to-many relation, the owner side is always many-to-one. -It means that the class that uses `@ManyToOne` will store the id of the related object. - -After you run the application, the ORM will create the `author` table: - - -```shell -+-------------+--------------+----------------------------+ -| author | -+-------------+--------------+----------------------------+ -| id | int(11) | PRIMARY KEY AUTO_INCREMENT | -| name | varchar(255) | | -+-------------+--------------+----------------------------+ -``` - -It will also modify the `photo` table, adding a new `author` column and creating a foreign key for it: - -```shell -+-------------+--------------+----------------------------+ -| photo | -+-------------+--------------+----------------------------+ -| id | int(11) | PRIMARY KEY AUTO_INCREMENT | -| name | varchar(255) | | -| description | varchar(255) | | -| filename | varchar(255) | | -| isPublished | boolean | | -| authorId | int(11) | FOREIGN KEY | -+-------------+--------------+----------------------------+ -``` - -### Creating a many-to-many relation - -Let's create a many-to-one / many-to-many relation. -Let's say a photo can be in many albums, and each album can contain many photos. -Let's create an `Album` class: - -```typescript -import {Entity, PrimaryGeneratedColumn, Column, ManyToMany, JoinTable} from "typeorm"; - -@Entity() -export class Album { - - @PrimaryGeneratedColumn() - id: number; - - @Column() - name: string; - - @ManyToMany(type => Photo, photo => photo.albums) - @JoinTable() - photos: Photo[]; -} -``` - -`@JoinTable` is required to specify that this is the owner side of the relationship. - -Now let's add the inverse side of our relation to the `Photo` class: - -```typescript -export class Photo { - /// ... other columns - - @ManyToMany(type => Album, album => album.photos) - albums: Album[]; -} -``` - -After you run the application, the ORM will create a **album_photos_photo_albums** *junction table*: - -```shell -+-------------+--------------+----------------------------+ -| album_photos_photo_albums | -+-------------+--------------+----------------------------+ -| album_id | int(11) | PRIMARY KEY FOREIGN KEY | -| photo_id | int(11) | PRIMARY KEY FOREIGN KEY | -+-------------+--------------+----------------------------+ -``` - -Don't forget to register the `Album` class with your connection in the ORM: - -```typescript -const options: ConnectionOptions = { - // ... other options - entities: [Photo, PhotoMetadata, Author, Album] -}; -``` - -Now let's insert albums and photos to our database: - -```typescript -let connection = await createConnection(options); - -// create a few albums -let album1 = new Album(); -album1.name = "Bears"; -await connection.manager.save(album1); - -let album2 = new Album(); -album2.name = "Me"; -await connection.manager.save(album2); - -// create a few photos -let photo = new Photo(); -photo.name = "Me and Bears"; -photo.description = "I am near polar bears"; -photo.filename = "photo-with-bears.jpg"; -photo.albums = [album1, album2]; -await connection.manager.save(photo); - -// now our photo is saved and albums are attached to it -// now lets load them: -const loadedPhoto = await connection - .getRepository(Photo) - .findOne(1, { relations: ["albums"] }); -``` - -`loadedPhoto` will be equal to: - -```typescript -{ - id: 1, - name: "Me and Bears", - description: "I am near polar bears", - filename: "photo-with-bears.jpg", - albums: [{ - id: 1, - name: "Bears" - }, { - id: 2, - name: "Me" - }] -} -``` - -### Using QueryBuilder - -You can use QueryBuilder to build SQL queries of almost any complexity. For example, you can do this: - -```typescript -let photos = await connection - .getRepository(Photo) - .createQueryBuilder("photo") // first argument is an alias. Alias is what you are selecting - photos. You must specify it. - .innerJoinAndSelect("photo.metadata", "metadata") - .leftJoinAndSelect("photo.albums", "album") - .where("photo.isPublished = true") - .andWhere("(photo.name = :photoName OR photo.name = :bearName)") - .orderBy("photo.id", "DESC") - .skip(5) - .take(10) - .setParameters({ photoName: "My", bearName: "Mishka" }) - .getMany(); -``` - -This query selects all published photos with "My" or "Mishka" names. -It will select results from position 5 (pagination offset), -and will select only 10 results (pagination limit). -The selection result will be ordered by id in descending order. -The photo's albums will be left-joined and their metadata will be inner joined. - -You'll use the query builder in your application a lot. -Learn more about QueryBuilder [here](./docs/select-query-builder.md). - -## Samples - -Take a look at the samples in [sample](https://github.com/typeorm/typeorm/tree/master/sample) for examples of usage. - -There are a few repositories which you can clone and start with: - -* [Example how to use TypeORM with TypeScript](https://github.com/typeorm/typescript-example) -* [Example how to use TypeORM with JavaScript](https://github.com/typeorm/javascript-example) -* [Example how to use TypeORM with JavaScript and Babel](https://github.com/typeorm/babel-example) -* [Example how to use TypeORM with TypeScript and SystemJS in Browser](https://github.com/typeorm/browser-example) -* [Example how to use Express and TypeORM](https://github.com/typeorm/typescript-express-example) -* [Example how to use Koa and TypeORM](https://github.com/typeorm/typescript-koa-example) -* [Example how to use TypeORM with MongoDB](https://github.com/typeorm/mongo-typescript-example) -* [Example how to use TypeORM in a Cordova/PhoneGap app](https://github.com/typeorm/cordova-example) -* [Example how to use TypeORM with an Ionic app](https://github.com/typeorm/ionic-example) -* [Example how to use TypeORM with React Native](https://github.com/typeorm/react-native-example) -* [Example how to use TypeORM with Electron using JavaScript](https://github.com/typeorm/electron-javascript-example) -* [Example how to use TypeORM with Electron using TypeScript](https://github.com/typeorm/electron-typescript-example) - -## Extensions - -There are several extensions that simplify working with TypeORM and integrating it with other modules: - -* [TypeORM + GraphQL framework](http://vesper-framework.com) -* [TypeORM integration](https://github.com/typeorm/typeorm-typedi-extensions) with [TypeDI](https://github.com/pleerock/typedi) -* [TypeORM integration](https://github.com/typeorm/typeorm-routing-controllers-extensions) with [routing-controllers](https://github.com/pleerock/routing-controllers) -* Models generation from existing database - [typeorm-model-generator](https://github.com/Kononnable/typeorm-model-generator) - -## Contributing - -Learn about contribution [here](https://github.com/typeorm/typeorm/blob/master/CONTRIBUTING.md) and how to setup your development environment [here](https://github.com/typeorm/typeorm/blob/master/DEVELOPER.md). - -This project exists thanks to all the people who contribute: - - - -## Sponsors - -Open source is hard and time-consuming. If you want to invest into TypeORM's future you can become a sponsor and make our core team to spend more time on TypeORM's improvements and new features. [Become a sponsor](https://opencollective.com/typeorm) - - - -## Gold Sponsors - -Become a gold sponsor and get a premium technical support from our core contributors. [Become a gold sponsor](https://opencollective.com/typeorm) - - +
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+ +TypeORM is an [ORM](https://en.wikipedia.org/wiki/Object-relational_mapping) +that can run in NodeJS, Browser, Cordova, PhoneGap, Ionic, React Native, NativeScript, Expo, and Electron platforms +and can be used with TypeScript and JavaScript (ES5, ES6, ES7, ES8). +Its goal is to always support the latest JavaScript features and provide additional features +that help you to develop any kind of application that uses databases - from +small applications with a few tables to large scale enterprise applications +with multiple databases. + +TypeORM supports both Active Record and Data Mapper patterns, +unlike all other JavaScript ORMs currently in existence, +which means you can write high quality, loosely coupled, scalable, +maintainable applications the most productive way. + +TypeORM is highly influenced by other ORMs, such as [Hibernate](http://hibernate.org/orm/), + [Doctrine](http://www.doctrine-project.org/) and [Entity Framework](https://www.asp.net/entity-framework). + +Some TypeORM features: + +* supports both DataMapper and ActiveRecord (your choice) +* entities and columns +* database-specific column types +* entity manager +* repositories and custom repositories +* clean object relational model +* associations (relations) +* eager and lazy relations +* uni-directional, bi-directional and self-referenced relations +* supports multiple inheritance patterns +* cascades +* indices +* transactions +* migrations and automatic migrations generation +* connection pooling +* replication +* using multiple database connections +* working with multiple databases types +* cross-database and cross-schema queries +* elegant-syntax, flexible and powerful QueryBuilder +* left and inner joins +* proper pagination for queries using joins +* query caching +* streaming raw results +* logging +* listeners and subscribers (hooks) +* supports closure table pattern +* schema declaration in models or separate configuration files +* connection configuration in json / xml / yml / env formats +* supports MySQL / MariaDB / Postgres / SQLite / Microsoft SQL Server / Oracle / sql.js +* supports MongoDB NoSQL database +* works in NodeJS / Browser / Ionic / Cordova / React Native / NativeScript / Expo / Electron platforms +* TypeScript and JavaScript support +* produced code is performant, flexible, clean and maintainable +* follows all possible best practices +* CLI + +And more... + +With TypeORM your models look like this: + +```typescript +import {Entity, PrimaryGeneratedColumn, Column} from "typeorm"; + +@Entity() +export class User { + + @PrimaryGeneratedColumn() + id: number; + + @Column() + firstName: string; + + @Column() + lastName: string; + + @Column() + age: number; + +} +``` + +And your domain logic looks like this: + +```typescript +const user = new User(); +user.firstName = "Timber"; +user.lastName = "Saw"; +user.age = 25; +await repository.save(user); + +const allUsers = await repository.find(); +const firstUser = await repository.findOne(1); // find by id +const timber = await repository.findOne({ firstName: "Timber", lastName: "Saw" }); + +await repository.remove(timber); +``` + +Alternatively, if you prefer to use the `ActiveRecord` implementation, you can use it as well: + +```typescript +import {Entity, PrimaryGeneratedColumn, Column, BaseEntity} from "typeorm"; + +@Entity() +export class User extends BaseEntity { + + @PrimaryGeneratedColumn() + id: number; + + @Column() + firstName: string; + + @Column() + lastName: string; + + @Column() + age: number; + +} +``` + +And your domain logic will look this way: + +```typescript +const user = new User(); +user.firstName = "Timber"; +user.lastName = "Saw"; +user.age = 25; +await user.save(); + +const allUsers = await User.find(); +const firstUser = await User.findOne(1); +const timber = await User.findOne({ firstName: "Timber", lastName: "Saw" }); + +await timber.remove(); +``` + +## Installation + + +1. Install the npm package: + + `npm install typeorm --save` + +2. You need to install `reflect-metadata` shim: + + `npm install reflect-metadata --save` + + and import it somewhere in the global place of your app (for example in `app.ts`): + + `import "reflect-metadata";` + +3. You may need to install node typings: + + `npm install @types/node --save` + +4. Install a database driver: + + * for **MySQL** or **MariaDB** + + `npm install mysql --save` (you can install `mysql2` instead as well) + + * for **PostgreSQL** + + `npm install pg --save` + + * for **SQLite** + + `npm install sqlite3 --save` + + * for **Microsoft SQL Server** + + `npm install mssql --save` + + * for **sql.js** + + `npm install sql.js --save` + + * for **Oracle** + + `npm install oracledb --save` + + Install only *one* of them, depending on which database you use. + + To make the Oracle driver work, you need to follow the installation instructions from + [their](https://github.com/oracle/node-oracledb) site. + + * for **MongoDB** (experimental) + + `npm install mongodb --save` + + * for **NativeScript**, **react-native** and **Cordova** + + Check [documentation of supported platforms](docs/supported-platforms.md) + + + +##### TypeScript configuration + +Also, make sure you are using TypeScript compiler version **2.3** or greater, +and you have enabled the following settings in `tsconfig.json`: + +```json +"emitDecoratorMetadata": true, +"experimentalDecorators": true, +``` + +You may also need to enable `es6` in the `lib` section of compiler options, or install `es6-shim` from `@types`. + +## Quick Start + +The quickest way to get started with TypeORM is to use its CLI commands to generate a starter project. +Quick start works only if you are using TypeORM in a NodeJS application. +If you are using other platforms, proceed to the [step-by-step guide](#step-by-step-guide). + +First, install TypeORM globally: + +``` +npm install typeorm -g +``` + +Then go to the directory where you want to create a new project and run the command: + +``` +typeorm init --name MyProject --database mysql +``` + +Where `name` is the name of your project and `database` is the database you'll use. +Database can be one of the following values: `mysql`, `mariadb`, `postgres`, `sqlite`, `mssql`, `oracle`, `mongodb`, +`cordova`, `react-native`, `expo`, `nativescript`. + +This command will generate a new project in the `MyProject` directory with the following files: + +``` +MyProject +├── src // place of your TypeScript code +│ ├── entity // place where your entities (database models) are stored +│ │ └── User.ts // sample entity +│ ├── migration // place where your migrations are stored +│ └── index.ts // start point of your application +├── .gitignore // standard gitignore file +├── ormconfig.json // ORM and database connection configuration +├── package.json // node module dependencies +├── README.md // simple readme file +└── tsconfig.json // TypeScript compiler options +``` + +> You can also run `typeorm init` on an existing node project, but be careful - it may override some files you already have. + +The next step is to install new project dependencies: + +``` +cd MyProject +npm install +``` + +While installation is in progress, edit the `ormconfig.json` file and put your own database connection configuration options in there: + +```json +{ + "type": "mysql", + "host": "localhost", + "port": 3306, + "username": "test", + "password": "test", + "database": "test", + "synchronize": true, + "logging": false, + "entities": [ + "src/entity/**/*.ts" + ], + "migrations": [ + "src/migration/**/*.ts" + ], + "subscribers": [ + "src/subscriber/**/*.ts" + ] +} +``` + +Particularly, most of the time you'll only need to configure +`host`, `username`, `password`, `database` and maybe `port` options. + +Once you finish with configuration and all node modules are installed, you can run your application: + +``` +npm start +``` + +That's it, your application should successfully run and insert a new user into the database. +You can continue to work with this project and integrate other modules you need and start +creating more entities. + +> You can generate an even more advanced project with express installed by running +`typeorm init --name MyProject --database mysql --express` command. + +## Step-by-Step Guide + +What are you expecting from ORM? +First of all, you are expecting it will create database tables for you +and find / insert / update / delete your data without the pain of +having to write lots of hardly maintainable SQL queries. +This guide will show you how to setup TypeORM from scratch and make it do what you are expecting from an ORM. + +### Create a model + +Working with a database starts from creating tables. +How do you tell TypeORM to create a database table? +The answer is - through the models. +Your models in your app are your database tables. + +For example, you have a `Photo` model: + +```typescript +export class Photo { + id: number; + name: string; + description: string; + filename: string; + views: number; +} +``` + +And you want to store photos in your database. +To store things in the database, first you need a database table, +and database tables are created from your models. +Not all models, but only those you define as *entities*. + +### Create an entity + +*Entity* is your model decorated by an `@Entity` decorator. +A database table will be created for such models. +You work with entities everywhere with TypeORM. +You can load/insert/update/remove and perform other operations with them. + +Let's make our `Photo` model as an entity: + +```typescript +import {Entity} from "typeorm"; + +@Entity() +export class Photo { + id: number; + name: string; + description: string; + filename: string; + views: number; + isPublished: boolean; +} +``` + +Now, a database table will be created for the `Photo` entity and we'll be able to work with it anywhere in our app. +We have created a database table, however what table can exist without columns? +Let's create a few columns in our database table. + +### Adding table columns + +To add database columns, you simply need to decorate an entity's properties you want to make into a column +with a `@Column` decorator. + +```typescript +import {Entity, Column} from "typeorm"; + +@Entity() +export class Photo { + + @Column() + id: number; + + @Column() + name: string; + + @Column() + description: string; + + @Column() + filename: string; + + @Column() + views: number; + + @Column() + isPublished: boolean; +} +``` + +Now `id`, `name`, `description`, `filename`, `views` and `isPublished` columns will be added to the `photo` table. +Column types in the database are inferred from the property types you used, e.g. +`number` will be converted into `integer`, `string` into `varchar`, `boolean` into `bool`, etc. +But you can use any column type your database supports by implicitly specifying a column type into the `@Column` decorator. + +We generated a database table with columns, but there is one thing left. +Each database table must have a column with a primary key. + +### Creating a primary column + +Each entity **must** have at least one primary key column. +This is a requirement and you can't avoid it. +To make a column a primary key, you need to use `@PrimaryColumn` decorator. + +```typescript +import {Entity, Column, PrimaryColumn} from "typeorm"; + +@Entity() +export class Photo { + + @PrimaryColumn() + id: number; + + @Column() + name: string; + + @Column() + description: string; + + @Column() + filename: string; + + @Column() + views: number; + + @Column() + isPublished: boolean; +} +``` + +### Creating an auto generated column + +Now, let's say you want your id column to be auto-generated (this is known as auto-increment / sequence / serial / generated identity column). +To do that, you need to change the `@PrimaryColumn` decorator to a `@PrimaryGeneratedColumn` decorator: + +```typescript +import {Entity, Column, PrimaryGeneratedColumn} from "typeorm"; + +@Entity() +export class Photo { + + @PrimaryGeneratedColumn() + id: number; + + @Column() + name: string; + + @Column() + description: string; + + @Column() + filename: string; + + @Column() + views: number; + + @Column() + isPublished: boolean; +} +``` + +### Column data types + +Next, let's fix our data types. By default, string is mapped to a varchar(255)-like type (depending on the database type). +Number is mapped to a integer-like type (depending on the database type). +We don't want all our columns to be limited varchars or integers. +Let's setup correct data types: + +```typescript +import {Entity, Column, PrimaryGeneratedColumn} from "typeorm"; + +@Entity() +export class Photo { + + @PrimaryGeneratedColumn() + id: number; + + @Column({ + length: 100 + }) + name: string; + + @Column("text") + description: string; + + @Column() + filename: string; + + @Column("double") + views: number; + + @Column() + isPublished: boolean; +} +``` + +Column types are database-specific. +You can set any column type your database supports. +More information on supported column types can be found [here](./docs/entities.md#column-types). + +### Creating a connection to the database + +Now, when our entity is created, let's create an `index.ts` (or `app.ts` whatever you call it) file and set up our connection there: + +```typescript +import "reflect-metadata"; +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; + +createConnection({ + type: "mysql", + host: "localhost", + port: 3306, + username: "root", + password: "admin", + database: "test", + entities: [ + Photo + ], + synchronize: true, + logging: false +}).then(connection => { + // here you can start to work with your entities +}).catch(error => console.log(error)); +``` + +We are using MySQL in this example, but you can use any other supported database. +To use another database, simply change the `type` in the options to the database type you are using: +mysql, mariadb, postgres, sqlite, mssql, oracle, cordova, nativescript, react-native, expo, or mongodb. +Also make sure to use your own host, port, username, password and database settings. + +We added our Photo entity to the list of entities for this connection. +Each entity you are using in your connection must be listed there. + +Setting `synchronize` makes sure your entities will be synced with the database, every time you run the application. + +### Loading all entities from the directory + +Later, when we create more entities we need to add them to the entities in our configuration. +This is not very convenient, so instead we can set up the whole directory, from where all entities will be connected and used in our connection: + +```typescript +import {createConnection} from "typeorm"; + +createConnection({ + type: "mysql", + host: "localhost", + port: 3306, + username: "root", + password: "admin", + database: "test", + entities: [ + __dirname + "/entity/*.js" + ], + synchronize: true, +}).then(connection => { + // here you can start to work with your entities +}).catch(error => console.log(error)); +``` + +But be careful with this approach. +If you are using `ts-node` then you need to specify paths to `.ts` files instead. +If you are using `outDir` then you'll need to specify paths to `.js` files inside outDir directory. +If you are using `outDir` and when you remove or rename your entities make sure to clear `outDir` directory +and re-compile your project again, because when you remove your source `.ts` files their compiled `.js` versions +aren't removed from output directory and still are loaded by TypeORM because they are present in the `outDir` directory. + +### Running the application + +Now if you run your `index.ts`, a connection with database will be initialized and a database table for your photos will be created. + + +```shell ++-------------+--------------+----------------------------+ +| photo | ++-------------+--------------+----------------------------+ +| id | int(11) | PRIMARY KEY AUTO_INCREMENT | +| name | varchar(500) | | +| description | text | | +| filename | varchar(255) | | +| views | int(11) | | +| isPublished | boolean | | ++-------------+--------------+----------------------------+ +``` + +### Creating and inserting a photo into the database + +Now let's create a new photo to save it in the database: + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; + +createConnection(/*...*/).then(connection => { + + let photo = new Photo(); + photo.name = "Me and Bears"; + photo.description = "I am near polar bears"; + photo.filename = "photo-with-bears.jpg"; + photo.views = 1; + photo.isPublished = true; + +    return connection.manager + .save(photo) + .then(photo => { + console.log("Photo has been saved. Photo id is", photo.id); + }); + +}).catch(error => console.log(error)); +``` + +Once your entity is saved it will get a newly generated id. +`save` method returns an instance of the same object you pass to it. +It's not a new copy of the object, it modifies its "id" and returns it. + +### Using async/await syntax + +Let's take advantage of the latest ES8 (ES2017) features and use async/await syntax instead: + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; + +createConnection(/*...*/).then(async connection => { + + let photo = new Photo(); + photo.name = "Me and Bears"; + photo.description = "I am near polar bears"; + photo.filename = "photo-with-bears.jpg"; + photo.views = 1; + photo.isPublished = true; + + await connection.manager.save(photo); + console.log("Photo has been saved"); + +}).catch(error => console.log(error)); +``` + +### Using Entity Manager + +We just created a new photo and saved it in the database. +We used `EntityManager` to save it. +Using entity manager you can manipulate any entity in your app. +For example, let's load our saved entity: + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; + +createConnection(/*...*/).then(async connection => { + + /*...*/ + let savedPhotos = await connection.manager.find(Photo); + console.log("All photos from the db: ", savedPhotos); + +}).catch(error => console.log(error)); +``` + +`savedPhotos` will be an array of Photo objects with the data loaded from the database. + +Learn more about EntityManager [here](./docs/working-with-entity-manager.md). + +### Using Repositories + +Now let's refactor our code and use `Repository` instead of `EntityManager`. +Each entity has its own repository which handles all operations with its entity. +When you deal with entities a lot, Repositories are more convenient to use than EntityManagers: + + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; + +createConnection(/*...*/).then(async connection => { + + let photo = new Photo(); + photo.name = "Me and Bears"; + photo.description = "I am near polar bears"; + photo.filename = "photo-with-bears.jpg"; + photo.views = 1; + photo.isPublished = true; + + let photoRepository = connection.getRepository(Photo); + + await photoRepository.save(photo); + console.log("Photo has been saved"); + + let savedPhotos = await photoRepository.find(); + console.log("All photos from the db: ", savedPhotos); + +}).catch(error => console.log(error)); +``` + +Learn more about Repository [here](./docs/working-with-repository.md). + +### Loading from the database + +Let's try more load operations using the Repository: + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; + +createConnection(/*...*/).then(async connection => { + + /*...*/ + let allPhotos = await photoRepository.find(); + console.log("All photos from the db: ", allPhotos); + + let firstPhoto = await photoRepository.findOne(1); + console.log("First photo from the db: ", firstPhoto); + + let meAndBearsPhoto = await photoRepository.findOne({ name: "Me and Bears" }); + console.log("Me and Bears photo from the db: ", meAndBearsPhoto); + + let allViewedPhotos = await photoRepository.find({ views: 1 }); + console.log("All viewed photos: ", allViewedPhotos); + + let allPublishedPhotos = await photoRepository.find({ isPublished: true }); + console.log("All published photos: ", allPublishedPhotos); + + let [allPhotos, photosCount] = await photoRepository.findAndCount(); + console.log("All photos: ", allPhotos); + console.log("Photos count: ", photosCount); + +}).catch(error => console.log(error)); +``` + +### Updating in the database + +Now let's load a single photo from the database, update it and save it: + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; + +createConnection(/*...*/).then(async connection => { + + /*...*/ + let photoToUpdate = await photoRepository.findOne(1); + photoToUpdate.name = "Me, my friends and polar bears"; + await photoRepository.save(photoToUpdate); + +}).catch(error => console.log(error)); +``` + +Now photo with `id = 1` will be updated in the database. + +### Removing from the database + +Now let's remove our photo from the database: + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; + +createConnection(/*...*/).then(async connection => { + + /*...*/ + let photoToRemove = await photoRepository.findOne(1); + await photoRepository.remove(photoToRemove); + +}).catch(error => console.log(error)); +``` + +Now photo with `id = 1` will be removed from the database. + +### Creating a one-to-one relation + +Let's create a one-to-one relation with another class. +Let's create a new class in `PhotoMetadata.ts`. This PhotoMetadata class is supposed to contain our photo's additional meta-information: + +```typescript +import {Entity, Column, PrimaryGeneratedColumn, OneToOne, JoinColumn} from "typeorm"; +import {Photo} from "./Photo"; + +@Entity() +export class PhotoMetadata { + + @PrimaryGeneratedColumn() + id: number; + + @Column("int") + height: number; + + @Column("int") + width: number; + + @Column() + orientation: string; + + @Column() + compressed: boolean; + + @Column() + comment: string; + + @OneToOne(type => Photo) + @JoinColumn() + photo: Photo; +} +``` + +Here, we are using a new decorator called `@OneToOne`. It allows us to create a one-to-one relationship between two entities. +`type => Photo` is a function that returns the class of the entity with which we want to make our relationship. +We are forced to use a function that returns a class, instead of using the class directly, because of the language specifics. +We can also write it as `() => Photo`, but we use `type => Photo` as a convention to increase code readability. +The type variable itself does not contain anything. + +We also add a `@JoinColumn` decorator, which indicates that this side of the relationship will own the relationship. +Relations can be unidirectional or bidirectional. +Only one side of relational can be owning. +Using `@JoinColumn` decorator is required on the owner side of the relationship. + +If you run the app, you'll see a newly generated table, and it will contain a column with a foreign key for the photo relation: + +```shell ++-------------+--------------+----------------------------+ +| photo_metadata | ++-------------+--------------+----------------------------+ +| id | int(11) | PRIMARY KEY AUTO_INCREMENT | +| height | int(11) | | +| width | int(11) | | +| comment | varchar(255) | | +| compressed | boolean | | +| orientation | varchar(255) | | +| photoId | int(11) | FOREIGN KEY | ++-------------+--------------+----------------------------+ +``` + +### Save a one-to-one relation + +Now let's save a photo, its metadata and attach them to each other. + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; +import {PhotoMetadata} from "./entity/PhotoMetadata"; + +createConnection(/*...*/).then(async connection => { + + // create a photo + let photo = new Photo(); + photo.name = "Me and Bears"; + photo.description = "I am near polar bears"; + photo.filename = "photo-with-bears.jpg"; + photo.isPublished = true; + + // create a photo metadata + let metadata = new PhotoMetadata(); + metadata.height = 640; + metadata.width = 480; + metadata.compressed = true; + metadata.comment = "cybershoot"; + metadata.orientation = "portait"; + metadata.photo = photo; // this way we connect them + + // get entity repositories + let photoRepository = connection.getRepository(Photo); + let metadataRepository = connection.getRepository(PhotoMetadata); + + // first we should save a photo + await photoRepository.save(photo); + + // photo is saved. Now we need to save a photo metadata + await metadataRepository.save(metadata); + + // done + console.log("Metadata is saved, and relation between metadata and photo is created in the database too"); + +}).catch(error => console.log(error)); +``` + +### Inverse side of the relationship + +Relations can be unidirectional or bidirectional. +Currently, our relation between PhotoMetadata and Photo is unidirectional. +The owner of the relation is PhotoMetadata, and Photo doesn't know anything about PhotoMetadata. +This makes it complicated to access PhotoMetadata from the Photo side. +To fix this issue we should add an inverse relation, and make relations between PhotoMetadata and Photo bidirectional. +Let's modify our entities: + +```typescript +import {Entity, Column, PrimaryGeneratedColumn, OneToOne, JoinColumn} from "typeorm"; +import {Photo} from "./Photo"; + +@Entity() +export class PhotoMetadata { + + /* ... other columns */ + + @OneToOne(type => Photo, photo => photo.metadata) + @JoinColumn() + photo: Photo; +} +``` + +```typescript +import {Entity, Column, PrimaryGeneratedColumn, OneToOne} from "typeorm"; +import {PhotoMetadata} from "./PhotoMetadata"; + +@Entity() +export class Photo { + + /* ... other columns */ + + @OneToOne(type => PhotoMetadata, photoMetadata => photoMetadata.photo) + metadata: PhotoMetadata; +} +``` + +`photo => photo.metadata` is a function that returns the name of the inverse side of the relation. +Here we show that the metadata property of the Photo class is where we store PhotoMetadata in the Photo class. +Instead of passing a function that returns a property of the photo, you could alternatively simply pass a string to `@OneToOne` decorator, like `"metadata"`. +But we used this function-typed approach to make our refactoring easier. + +Note that we should use `@JoinColumn` decorator only on one side of a relation. +Whichever side you put this decorator on will be the owning side of the relationship. +The owning side of a relationship contains a column with a foreign key in the database. + +### Loading objects with their relations + +Now let's load our photo and its photo metadata in a single query. +There are two ways to do it - using `find*` methods or using `QueryBuilder` functionality. +Let's use `find*` methods first. +`find*` methods allow you to specify an object with the `FindOneOptions` / `FindManyOptions` interface. + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; +import {PhotoMetadata} from "./entity/PhotoMetadata"; + +createConnection(/*...*/).then(async connection => { + + /*...*/ + let photoRepository = connection.getRepository(Photo); + let photos = await photoRepository.find({ relations: ["metadata"] }); + +}).catch(error => console.log(error)); +``` + +Here, photos will contain an array of photos from the database, and each photo will contain its photo metadata. +Learn more about Find Options in [this documentation](./docs/find-options.md). + +Using find options is good and dead simple, but if you need a more complex query, you should use `QueryBuilder` instead. +`QueryBuilder` allows more complex queries to be used in an elegant way: + +```typescript +import {createConnection} from "typeorm"; +import {Photo} from "./entity/Photo"; +import {PhotoMetadata} from "./entity/PhotoMetadata"; + +createConnection(/*...*/).then(async connection => { + + /*...*/ + let photos = await connection + .getRepository(Photo) + .createQueryBuilder("photo") + .innerJoinAndSelect("photo.metadata", "metadata") + .getMany(); + + +}).catch(error => console.log(error)); +``` + +`QueryBuilder` allows creation and execution of SQL queries of almost any complexity. +When you work with `QueryBuilder`, think like you are creating an SQL query. +In this example, "photo" and "metadata" are aliases applied to selected photos. +You use aliases to access columns and properties of the selected data. + +### Using cascades to automatically save related objects + +We can setup cascade options in our relations, in the cases when we want our related object to be saved whenever the other object is saved. +Let's change our photo's `@OneToOne` decorator a bit: + +```typescript +export class Photo { + /// ... other columns + + @OneToOne(type => PhotoMetadata, metadata => metadata.photo, { + cascade: true, + }) + metadata: PhotoMetadata; +} +``` + +Using `cascade` allows us not to separately save photo and separately save metadata objects now. +Now we can simply save a photo object, and the metadata object will be saved automatically because of cascade options. + +```typescript +createConnection(options).then(async connection => { + + // create photo object + let photo = new Photo(); + photo.name = "Me and Bears"; + photo.description = "I am near polar bears"; + photo.filename = "photo-with-bears.jpg"; + photo.isPublished = true; + + // create photo metadata object + let metadata = new PhotoMetadata(); + metadata.height = 640; + metadata.width = 480; + metadata.compressed = true; + metadata.comment = "cybershoot"; + metadata.orientation = "portait"; + + photo.metadata = metadata; // this way we connect them + + // get repository + let photoRepository = connection.getRepository(Photo); + + // saving a photo also save the metadata + await photoRepository.save(photo); + + console.log("Photo is saved, photo metadata is saved too.") + +}).catch(error => console.log(error)); +``` + +### Creating a many-to-one / one-to-many relation + +Let's create a many-to-one / one-to-many relation. +Let's say a photo has one author, and each author can have many photos. +First, let's create an `Author` class: + +```typescript +import {Entity, Column, PrimaryGeneratedColumn, OneToMany, JoinColumn} from "typeorm"; +import {Photo} from "./Photo"; + +@Entity() +export class Author { + + @PrimaryGeneratedColumn() + id: number; + + @Column() + name: string; + + @OneToMany(type => Photo, photo => photo.author) // note: we will create author property in the Photo class below + photos: Photo[]; +} +``` + +`Author` contains an inverse side of a relation. +`OneToMany` is always an inverse side of relation, and it can't exist without `ManyToOne` on the other side of the relation. + +Now let's add the owner side of the relation into the Photo entity: + +```typescript +import {Entity, Column, PrimaryGeneratedColumn, ManyToOne} from "typeorm"; +import {PhotoMetadata} from "./PhotoMetadata"; +import {Author} from "./Author"; + +@Entity() +export class Photo { + + /* ... other columns */ + + @ManyToOne(type => Author, author => author.photos) + author: Author; +} +``` + +In many-to-one / one-to-many relation, the owner side is always many-to-one. +It means that the class that uses `@ManyToOne` will store the id of the related object. + +After you run the application, the ORM will create the `author` table: + + +```shell ++-------------+--------------+----------------------------+ +| author | ++-------------+--------------+----------------------------+ +| id | int(11) | PRIMARY KEY AUTO_INCREMENT | +| name | varchar(255) | | ++-------------+--------------+----------------------------+ +``` + +It will also modify the `photo` table, adding a new `author` column and creating a foreign key for it: + +```shell ++-------------+--------------+----------------------------+ +| photo | ++-------------+--------------+----------------------------+ +| id | int(11) | PRIMARY KEY AUTO_INCREMENT | +| name | varchar(255) | | +| description | varchar(255) | | +| filename | varchar(255) | | +| isPublished | boolean | | +| authorId | int(11) | FOREIGN KEY | ++-------------+--------------+----------------------------+ +``` + +### Creating a many-to-many relation + +Let's create a many-to-one / many-to-many relation. +Let's say a photo can be in many albums, and each album can contain many photos. +Let's create an `Album` class: + +```typescript +import {Entity, PrimaryGeneratedColumn, Column, ManyToMany, JoinTable} from "typeorm"; + +@Entity() +export class Album { + + @PrimaryGeneratedColumn() + id: number; + + @Column() + name: string; + + @ManyToMany(type => Photo, photo => photo.albums) + @JoinTable() + photos: Photo[]; +} +``` + +`@JoinTable` is required to specify that this is the owner side of the relationship. + +Now let's add the inverse side of our relation to the `Photo` class: + +```typescript +export class Photo { + /// ... other columns + + @ManyToMany(type => Album, album => album.photos) + albums: Album[]; +} +``` + +After you run the application, the ORM will create a **album_photos_photo_albums** *junction table*: + +```shell ++-------------+--------------+----------------------------+ +| album_photos_photo_albums | ++-------------+--------------+----------------------------+ +| album_id | int(11) | PRIMARY KEY FOREIGN KEY | +| photo_id | int(11) | PRIMARY KEY FOREIGN KEY | ++-------------+--------------+----------------------------+ +``` + +Don't forget to register the `Album` class with your connection in the ORM: + +```typescript +const options: ConnectionOptions = { + // ... other options + entities: [Photo, PhotoMetadata, Author, Album] +}; +``` + +Now let's insert albums and photos to our database: + +```typescript +let connection = await createConnection(options); + +// create a few albums +let album1 = new Album(); +album1.name = "Bears"; +await connection.manager.save(album1); + +let album2 = new Album(); +album2.name = "Me"; +await connection.manager.save(album2); + +// create a few photos +let photo = new Photo(); +photo.name = "Me and Bears"; +photo.description = "I am near polar bears"; +photo.filename = "photo-with-bears.jpg"; +photo.albums = [album1, album2]; +await connection.manager.save(photo); + +// now our photo is saved and albums are attached to it +// now lets load them: +const loadedPhoto = await connection + .getRepository(Photo) + .findOne(1, { relations: ["albums"] }); +``` + +`loadedPhoto` will be equal to: + +```typescript +{ + id: 1, + name: "Me and Bears", + description: "I am near polar bears", + filename: "photo-with-bears.jpg", + albums: [{ + id: 1, + name: "Bears" + }, { + id: 2, + name: "Me" + }] +} +``` + +### Using QueryBuilder + +You can use QueryBuilder to build SQL queries of almost any complexity. For example, you can do this: + +```typescript +let photos = await connection + .getRepository(Photo) + .createQueryBuilder("photo") // first argument is an alias. Alias is what you are selecting - photos. You must specify it. + .innerJoinAndSelect("photo.metadata", "metadata") + .leftJoinAndSelect("photo.albums", "album") + .where("photo.isPublished = true") + .andWhere("(photo.name = :photoName OR photo.name = :bearName)") + .orderBy("photo.id", "DESC") + .skip(5) + .take(10) + .setParameters({ photoName: "My", bearName: "Mishka" }) + .getMany(); +``` + +This query selects all published photos with "My" or "Mishka" names. +It will select results from position 5 (pagination offset), +and will select only 10 results (pagination limit). +The selection result will be ordered by id in descending order. +The photo's albums will be left-joined and their metadata will be inner joined. + +You'll use the query builder in your application a lot. +Learn more about QueryBuilder [here](./docs/select-query-builder.md). + +## Samples + +Take a look at the samples in [sample](https://github.com/typeorm/typeorm/tree/master/sample) for examples of usage. + +There are a few repositories which you can clone and start with: + +* [Example how to use TypeORM with TypeScript](https://github.com/typeorm/typescript-example) +* [Example how to use TypeORM with JavaScript](https://github.com/typeorm/javascript-example) +* [Example how to use TypeORM with JavaScript and Babel](https://github.com/typeorm/babel-example) +* [Example how to use TypeORM with TypeScript and SystemJS in Browser](https://github.com/typeorm/browser-example) +* [Example how to use Express and TypeORM](https://github.com/typeorm/typescript-express-example) +* [Example how to use Koa and TypeORM](https://github.com/typeorm/typescript-koa-example) +* [Example how to use TypeORM with MongoDB](https://github.com/typeorm/mongo-typescript-example) +* [Example how to use TypeORM in a Cordova/PhoneGap app](https://github.com/typeorm/cordova-example) +* [Example how to use TypeORM with an Ionic app](https://github.com/typeorm/ionic-example) +* [Example how to use TypeORM with React Native](https://github.com/typeorm/react-native-example) +* [Example how to use TypeORM with Electron using JavaScript](https://github.com/typeorm/electron-javascript-example) +* [Example how to use TypeORM with Electron using TypeScript](https://github.com/typeorm/electron-typescript-example) + +## Extensions + +There are several extensions that simplify working with TypeORM and integrating it with other modules: + +* [TypeORM + GraphQL framework](http://vesper-framework.com) +* [TypeORM integration](https://github.com/typeorm/typeorm-typedi-extensions) with [TypeDI](https://github.com/pleerock/typedi) +* [TypeORM integration](https://github.com/typeorm/typeorm-routing-controllers-extensions) with [routing-controllers](https://github.com/pleerock/routing-controllers) +* Models generation from existing database - [typeorm-model-generator](https://github.com/Kononnable/typeorm-model-generator) + +## Contributing + +Learn about contribution [here](https://github.com/typeorm/typeorm/blob/master/CONTRIBUTING.md) and how to setup your development environment [here](https://github.com/typeorm/typeorm/blob/master/DEVELOPER.md). + +This project exists thanks to all the people who contribute: + + + +## Sponsors + +Open source is hard and time-consuming. If you want to invest into TypeORM's future you can become a sponsor and make our core team to spend more time on TypeORM's improvements and new features. [Become a sponsor](https://opencollective.com/typeorm) + + + +## Gold Sponsors + +Become a gold sponsor and get a premium technical support from our core contributors. [Become a gold sponsor](https://opencollective.com/typeorm) + +