diff --git a/index.js b/index.js
index ac2fd64c..b2863dde 100644
--- a/index.js
+++ b/index.js
@@ -21,13 +21,6 @@ function parse(str) {
   var result = url.parse(str, true);
   config = {};
 
-  if (result.query.application_name) {
-    config.application_name = result.query.application_name;
-  }
-  if (result.query.fallback_application_name) {
-    config.fallback_application_name = result.query.fallback_application_name;
-  }
-
   config.port = result.port;
   if(result.protocol == 'socket:') {
     config.host = decodeURI(result.pathname);
@@ -54,6 +47,18 @@ function parse(str) {
     config.ssl = true;
   }
 
+  ['db', 'database', 'encoding', 'client_encoding', 'host', 'port', 'user', 'password', 'ssl']
+  .forEach(function(key) {
+    delete result.query[key];
+  });
+
+  Object.getOwnPropertyNames(result.query).forEach(function(key) {
+    var value = result.query[key];
+    if (Array.isArray(value))
+      value = value[value.length-1];
+    config[key] = value;
+  });
+
   return config;
 }
 
diff --git a/test/parse.js b/test/parse.js
index c1494c31..bd1171ba 100644
--- a/test/parse.js
+++ b/test/parse.js
@@ -124,3 +124,67 @@ test('pathname of "/" returns null database', function (t) {
 
   t.end();
 });
+
+test('configuration parameter application_name', function(t){
+  var connectionString = 'pg:///?application_name=TheApp';
+  var subject = parse(connectionString);
+  t.equal(subject.application_name, 'TheApp');
+  t.end();
+});
+
+test('configuration parameter fallback_application_name', function(t){
+  var connectionString = 'pg:///?fallback_application_name=TheAppFallback';
+  var subject = parse(connectionString);
+  t.equal(subject.fallback_application_name, 'TheAppFallback');
+  t.end();
+});
+
+test('configuration parameter fallback_application_name', function(t){
+  var connectionString = 'pg:///?fallback_application_name=TheAppFallback';
+  var subject = parse(connectionString);
+  t.equal(subject.fallback_application_name, 'TheAppFallback');
+  t.end();
+});
+
+test('configuration parameter ssl=true', function(t){
+  var connectionString = 'pg:///?ssl=true';
+  var subject = parse(connectionString);
+  t.equal(subject.ssl, true);
+  t.end();
+});
+
+test('configuration parameter ssl=1', function(t){
+  var connectionString = 'pg:///?ssl=1';
+  var subject = parse(connectionString);
+  t.equal(subject.ssl, true);
+  t.end();
+});
+
+test('configuration parameter keepalives', function(t){
+  var connectionString = 'pg:///?keepalives=1';
+  var subject = parse(connectionString);
+  t.equal(subject.keepalives, '1');
+  t.end();
+});
+
+test('unknown configuration parameter is passed into client', function(t){
+  var connectionString = 'pg:///?ThereIsNoSuchPostgresParameter=1234';
+  var subject = parse(connectionString);
+  t.equal(subject.ThereIsNoSuchPostgresParameter, '1234');
+  t.end();
+});
+
+test('do not override a config field with value from query string', function(t){
+  var subject = parse('socket:/some path/?db=my[db]&encoding=utf8&client_encoding=bogus');
+  t.equal(subject.host, '/some path/');
+  t.equal(subject.database, 'my[db]', 'must to be escaped and unescaped trough "my%5Bdb%5D"');
+  t.equal(subject.client_encoding, 'utf8');
+  t.end();
+});
+
+test('return last value of repeated parameter', function(t){
+  var connectionString = 'pg:///?keepalives=1&keepalives=0';
+  var subject = parse(connectionString);
+  t.equal(subject.keepalives, '0');
+  t.end();
+});
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