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40 lines
947 B
Plaintext
40 lines
947 B
Plaintext
---
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title: Callbacks
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---
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## Callback Support
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`async` / `await` is the preferred way to write async code these days with node, but callbacks are supported in the `pg` module and the `pg-pool` module. To use them, pass a callback function as the last argument to the following methods & it will be called and a promise will not be returned:
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```js
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const { Pool, Client } = require('pg')
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// pool
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const pool = new Pool()
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// run a query on an available client
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pool.query('SELECT NOW()', (err, res) => {
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console.log(err, res)
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})
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// check out a client to do something more complex like a transaction
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pool.connect((err, client, release) => {
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client.query('SELECT NOW()', (err, res) => {
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release()
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console.log(err, res)
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pool.end()
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})
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})
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// single client
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const client = new Client()
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client.connect((err) => {
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if (err) throw err
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client.query('SELECT NOW()', (err, res) => {
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console.log(err, res)
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client.end()
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})
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})
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```
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