Cara menggunakan javascript query execute
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Sometimes I may also ask you to install the latest version from Github to check if a bugfix is working. In this case, please do: Show
$ npm install mysqljs/mysql IntroductionThis is a node.js driver for mysql. It is written in JavaScript, does not require compiling, and is 100% MIT licensed. Here is an example on how to use it: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end(); From this example, you can learn the following:
ContributorsThanks goes to the people who have contributed code to this module, see the GitHub Contributors page. Additionally I'd like to thank the following people:
SponsorsThe following companies have supported this project financially, allowing me to spend more time on it (ordered by time of contribution):
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Establishing connectionsThe recommended way to establish a connection is this: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); }); However, a connection can also be implicitly established by invoking a query: var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! }); Depending on how you like to handle your errors, either method may be appropriate. Any type of connection error (handshake or network) is considered a fatal error, see the section for more information. Connection optionsWhen establishing a connection, you can set the following options:
In addition to passing these options as an object, you can also use a url string. For example: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700'); Note: The query values are first attempted to be parsed as JSON, and if that fails assumed to be plaintext strings. SSL optionsThe $ npm install mysqljs/mysql25 option in the connection options takes a string or an object. When given a string, it uses one of the predefined SSL profiles included. The following profiles are included:
When connecting to other servers, you will need to provide an object with any of the following options:
Here is a simple example: var connection = mysql.createConnection({ host : 'localhost', ssl : { ca : fs.readFileSync(__dirname + '/mysql-ca.crt') } }); You can also connect to a MySQL server without properly providing the appropriate CA to trust. You should not do this. var connection = mysql.createConnection({ host : 'localhost', ssl : { // DO NOT DO THIS // set up your ca correctly to trust the connection rejectUnauthorized: false } }); Connection flagsIf, for any reason, you would like to change the default connection flags, you can use the connection option $ npm install mysqljs/mysql24. Pass a string with a comma separated list of items to add to the default flags. If you don't want a default flag to be used prepend the flag with a minus sign. To add a flag that is not in the default list, just write the flag name, or prefix it with a plus (case insensitive). var connection = mysql.createConnection({ // disable FOUND_ROWS flag, enable IGNORE_SPACE flag flags: '-FOUND_ROWS,IGNORE_SPACE' }); The following flags are available:
Terminating connectionsThere are two ways to end a connection. Terminating a connection gracefully is done by calling the var connection = mysql.createConnection({ host : 'localhost', ssl : { ca : fs.readFileSync(__dirname + '/mysql-ca.crt') } });5 method: connection.end(function(err) { // The connection is terminated now }); This will make sure all previously enqueued queries are still executed before sending a $ npm install mysqljs/mysql88 packet to the MySQL server. If a fatal error occurs before the $ npm install mysqljs/mysql88 packet can be sent, an $ npm install mysqljs/mysql90 argument will be provided to the callback, but the connection will be terminated regardless of that. An alternative way to end the connection is to call the $ npm install mysqljs/mysql91 method. This will cause an immediate termination of the underlying socket. Additionally $ npm install mysqljs/mysql91 guarantees that no more events or callbacks will be triggered for the connection. $ npm install mysqljs/mysql0 Unlike var connection = mysql.createConnection({ host : 'localhost', ssl : { ca : fs.readFileSync(__dirname + '/mysql-ca.crt') } });5 the $ npm install mysqljs/mysql91 method does not take a callback argument. Pooling connectionsRather than creating and managing connections one-by-one, this module also provides built-in connection pooling using $ npm install mysqljs/mysql95. Read more about connection pooling. Create a pool and use it directly: $ npm install mysqljs/mysql1 This is a shortcut for the $ npm install mysqljs/mysql96 -> $ npm install mysqljs/mysql97 -> $ npm install mysqljs/mysql98 code flow. Using $ npm install mysqljs/mysql96 is useful to share connection state for subsequent queries. This is because two calls to var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();00 may use two different connections and run in parallel. This is the basic structure: $ npm install mysqljs/mysql2 If you would like to close the connection and remove it from the pool, use var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();01 instead. The pool will create a new connection the next time one is needed. Connections are lazily created by the pool. If you configure the pool to allow up to 100 connections, but only ever use 5 simultaneously, only 5 connections will be made. Connections are also cycled round-robin style, with connections being taken from the top of the pool and returning to the bottom. When a previous connection is retrieved from the pool, a ping packet is sent to the server to check if the connection is still good. Pool optionsPools accept all the same . When creating a new connection, the options are simply passed to the connection constructor. In addition to those options pools accept a few extras:
Pool eventsacquireThe pool will emit an var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();15 event when a connection is acquired from the pool. This is called after all acquiring activity has been performed on the connection, right before the connection is handed to the callback of the acquiring code. $ npm install mysqljs/mysql3 connectionThe pool will emit a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();16 event when a new connection is made within the pool. If you need to set session variables on the connection before it gets used, you can listen to the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();16 event. $ npm install mysqljs/mysql4 enqueueThe pool will emit an var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();18 event when a callback has been queued to wait for an available connection. $ npm install mysqljs/mysql5 releaseThe pool will emit a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();19 event when a connection is released back to the pool. This is called after all release activity has been performed on the connection, so the connection will be listed as free at the time of the event. $ npm install mysqljs/mysql6 Closing all the connections in a poolWhen you are done using the pool, you have to end all the connections or the Node.js event loop will stay active until the connections are closed by the MySQL server. This is typically done if the pool is used in a script or when trying to gracefully shutdown a server. To end all the connections in the pool, use the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();20 method on the pool: $ npm install mysqljs/mysql7 The var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();20 method takes an optional callback that you can use to know when all the connections are ended. Once var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();22 is called, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();23 and other operations can no longer be performed. Wait until all connections in the pool are released before calling var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();22. If you use the shortcut method var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();25, in place of var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();23 → var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();27 → var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();28, wait until it completes. var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();22 calls var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();30 on every active connection in the pool. This queues a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();31 packet on the connection and sets a flag to prevent var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();23 from creating new connections. All commands / queries already in progress will complete, but new commands won't execute. PoolClusterPoolCluster provides multiple hosts connection. (group & retry & selector) $ npm install mysqljs/mysql8 PoolCluster options
$ npm install mysqljs/mysql9 Switching users and altering connection stateMySQL offers a changeUser command that allows you to alter the current user and other aspects of the connection without shutting down the underlying socket: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();0 The available options for this feature are:
A sometimes useful side effect of this functionality is that this function also resets any connection state (variables, transactions, etc.). Errors encountered during this operation are treated as fatal connection errors by this module. Server disconnectsYou may lose the connection to a MySQL server due to network problems, the server timing you out, the server being restarted, or crashing. All of these events are considered fatal errors, and will have the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();55. See the section for more information. Re-connecting a connection is done by establishing a new connection. Once terminated, an existing connection object cannot be re-connected by design. With Pool, disconnected connections will be removed from the pool freeing up space for a new connection to be created on the next getConnection call. With PoolCluster, disconnected connections will count as errors against the related node, incrementing the error code for that node. Once there are more than var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();37 errors on a given node, it is removed from the cluster. When this occurs, the PoolCluster may emit a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();57 error if there are no longer any matching nodes for the pattern. The var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();43 config can be set to restore offline nodes after a given timeout. Performing queriesThe most basic way to perform a query is to call the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();59 method on an object (like a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();60, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();61, or var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();62 instance). The simplest form of var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();59 is var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();64, where a SQL string is the first argument and the second is a callback: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();1 The second form var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();65 comes when using placeholder values (see ): var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();2 The third form var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();66 comes when using various advanced options on the query, like , , , and . var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();3 Note that a combination of the second and third forms can be used where the placeholder values are passed as an argument and not in the options object. The var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();67 argument will override the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();67 in the option object. var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();4 If the query only has a single replacement character ( var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();69), and the value is not var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();70, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();71, or an array, it can be passed directly as the second argument to var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();72: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();5 Escaping query valuesCaution These methods of escaping values only works when the SQL mode is disabled (which is the default state for MySQL servers). Caution This library performs client-side escaping, as this is a library to generate SQL strings on the client side. The syntax for functions like var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();73 may look similar to a prepared statement, but it is not and the escaping rules from this module are used to generate a resulting SQL string. The purpose of escaping input is to avoid SQL Injection attacks. In order to support enhanced support like var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();74 and var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();75 formatting, this module will escape based on the shape of the passed in JavaScript value, and the resulting escaped string may be more than a single value. When structured user input is provided as the value to escape, care should be taken to validate the shape of the input to validate the output will be what is expected. In order to avoid SQL Injection attacks, you should always escape any user provided data before using it inside a SQL query. You can do so using the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();76, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();77 or var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();78 methods: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();6 Alternatively, you can use var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();69 characters as placeholders for values you would like to have escaped like this: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();7 Multiple placeholders are mapped to values in the same order as passed. For example, in the following query var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();80 equals var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();81, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();82 equals var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();83, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();84 equals var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();85, and var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();86 will be var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();87: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();8 This looks similar to prepared statements in MySQL, however it really just uses the same var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();77 method internally. Caution This also differs from prepared statements in that all var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();69 are replaced, even those contained in comments and strings. Different value types are escaped differently, here is how:
This escaping allows you to do neat things like this: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();9 And the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();98 method allows you to form complex queries with functions: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });0 To generate objects with a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();98 method, the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });08 method can be used. This creates an object that will be left un-touched when using in a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();69 placeholder, useful for using functions as dynamic values: Caution The string provided to var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });08 will skip all escaping functions when used, so be careful when passing in unvalidated input. var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });1 If you feel the need to escape queries by yourself, you can also use the escaping function directly: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });2 Escaping query identifiersIf you can't trust an SQL identifier (database / table / column name) because it is provided by a user, you should escape it with var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });11, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });12 or var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });13 like this: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });3 It also supports adding qualified identifiers. It will escape both parts. var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });4 If you do not want to treat var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });14 as qualified identifiers, you can set the second argument to connection.end(function(err) { // The connection is terminated now });6 in order to keep the string as a literal identifier: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });5 Alternatively, you can use var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });16 characters as placeholders for identifiers you would like to have escaped like this: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });6 Please note that this last character sequence is experimental and syntax might change When you pass an Object to var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });17 or var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'localhost', user : 'me', password : 'secret', database : 'my_db' }); connection.connect(); connection.query('SELECT 1 + 1 AS solution', function (error, results, fields) { if (error) throw error; console.log('The solution is: ', results[0].solution); }); connection.end();59, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });19 is used to avoid SQL injection in object keys. Preparing QueriesYou can use mysql.format to prepare a query with multiple insertion points, utilizing the proper escaping for ids and values. A simple example of this follows: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });7 Following this you then have a valid, escaped query that you can then send to the database safely. This is useful if you are looking to prepare the query before actually sending it to the database. As mysql.format is exposed from SqlString.format you also have the option (but are not required) to pass in stringifyObject and timezone, allowing you provide a custom means of turning objects into strings, as well as a location-specific/timezone-aware Date. Custom formatIf you prefer to have another type of query escape format, there's a connection configuration option you can use to define a custom format function. You can access the connection object if you want to use the built-in var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });17 or any other connection function. Here's an example of how to implement another format: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });8 Getting the id of an inserted rowIf you are inserting a row into a table with an auto increment primary key, you can retrieve the insert id like this: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });9 When dealing with big numbers (above JavaScript Number precision limit), you should consider enabling connection.end(function(err) { // The connection is terminated now });8 option to be able to read the insert id as a string, otherwise it will throw an error. This option is also required when fetching big numbers from the database, otherwise you will get values rounded to hundreds or thousands due to the precision limit. Getting the number of affected rowsYou can get the number of affected rows from an insert, update or delete statement. var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });0 Getting the number of changed rowsYou can get the number of changed rows from an update statement. "changedRows" differs from "affectedRows" in that it does not count updated rows whose values were not changed. var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });1 Getting the connection IDYou can get the MySQL connection ID ("thread ID") of a given connection using the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });22 property. var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });2 Executing queries in parallelThe MySQL protocol is sequential, this means that you need multiple connections to execute queries in parallel. You can use a Pool to manage connections, one simple approach is to create one connection per incoming http request. Streaming query rowsSometimes you may want to select large quantities of rows and process each of them as they are received. This can be done like this: var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });3 Please note a few things about the example above:
Additionally you may be interested to know that it is currently not possible to stream individual row columns, they will always be buffered up entirely. If you have a good use case for streaming large fields to and from MySQL, I'd love to get your thoughts and contributions on this. Piping results with StreamsThe query object provides a convenience method var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });31 that wraps query events into a object. This stream can easily be piped downstream and provides automatic pause/resume, based on downstream congestion and the optional var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });32. The var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });33 parameter of the stream is set to connection.end(function(err) { // The connection is terminated now });6 and cannot be changed (if you need a byte stream, you will need to use a transform stream, like objstream for example). For example, piping query results into another stream (with a max buffer of 5 objects) is simply: var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });4 Multiple statement queriesSupport for multiple statements is disabled for security reasons (it allows for SQL injection attacks if values are not properly escaped). To use this feature you have to enable it for your connection: var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });5 Once enabled, you can execute multiple statement queries like any other query: var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });6 Additionally you can also stream the results of multiple statement queries: var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });7 If one of the statements in your query causes an error, the resulting Error object contains a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });35 property which tells you which statement caused it. MySQL will also stop executing any remaining statements when an error occurs. Please note that the interface for streaming multiple statement queries is experimental and I am looking forward to feedback on it. Stored proceduresYou can call stored procedures from your queries as with any other mysql driver. If the stored procedure produces several result sets, they are exposed to you the same way as the results for multiple statement queries. Joins with overlapping column namesWhen executing joins, you are likely to get result sets with overlapping column names. By default, node-mysql will overwrite colliding column names in the order the columns are received from MySQL, causing some of the received values to be unavailable. However, you can also specify that you want your columns to be nested below the table name like this: var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });8 Or use a string separator to have your results merged. var mysql = require('mysql'); var connection = mysql.createConnection(...); connection.query('SELECT 1', function (error, results, fields) { if (error) throw error; // connected! });9 TransactionsSimple transaction support is available at the connection level: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');0 Please note that beginTransaction(), commit() and rollback() are simply convenience functions that execute the START TRANSACTION, COMMIT, and ROLLBACK commands respectively. It is important to understand that many commands in MySQL can cause an implicit commit, as described in the MySQL documentation PingA ping packet can be sent over a connection using the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });36 method. This method will send a ping packet to the server and when the server responds, the callback will fire. If an error occurred, the callback will fire with an error argument. var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');1 TimeoutsEvery operation takes an optional inactivity timeout option. This allows you to specify appropriate timeouts for operations. It is important to note that these timeouts are not part of the MySQL protocol, and rather timeout operations through the client. This means that when a timeout is reached, the connection it occurred on will be destroyed and no further operations can be performed. var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');2 Error handlingThis module comes with a consistent approach to error handling that you should review carefully in order to write solid applications. Most errors created by this module are instances of the JavaScript Error object. Additionally they typically come with two extra properties:
Fatal errors are propagated to all pending callbacks. In the example below, a fatal error is triggered by trying to connect to a blocked port. Therefore the error object is propagated to both pending callbacks: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');3 Normal errors however are only delegated to the callback they belong to. So in the example below, only the first callback receives an error, the second query works as expected: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');4 Last but not least: If a fatal errors occurs and there are no pending callbacks, or a normal error occurs which has no callback belonging to it, the error is emitted as an var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });46 event on the connection object. This is demonstrated in the example below: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');5 Note: var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });46 events are special in node. If they occur without an attached listener, a stack trace is printed and your process is killed. tl;dr: This module does not want you to deal with silent failures. You should always provide callbacks to your method calls. If you want to ignore this advice and suppress unhandled errors, you can do this: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');6 Exception SafetyThis module is exception safe. That means you can continue to use it, even if one of your callback functions throws an error which you're catching using 'uncaughtException' or a domain. Type castingFor your convenience, this driver will cast mysql types into native JavaScript types by default. The default behavior can be changed through various . The following mappings exist: Number
Date
Buffer
StringNote text in the binary character set is returned as var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });48, rather than a string.
It is not recommended (and may go away / change in the future) to disable type casting, but you can currently do so on either the connection: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');7 Or on the query level: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');8 Custom type castingYou can also pass a function and handle type casting yourself. You're given some column information like database, table and name and also type and length. If you just want to apply a custom type casting to a specific type you can do it and then fallback to the default. The function is provided two arguments var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });49 and var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });50 and is expected to return the value for the given field by invoking the parser functions through the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });49 object. The var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });49 argument is a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });53 object and contains data about the field that need to be parsed. The following are some of the properties on a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });53 object:
The var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });50 argument is a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });61 that, when called, will return the default type conversion for the given field. When getting the field data, the following helper methods are present on the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });49 object:
The MySQL protocol is a text-based protocol. This means that over the wire, all field types are represented as a string, which is why only string-like functions are available on the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });49 object. Based on the type information (like var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });68), the type cast should convert the string field into a different JavaScript type (like a var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });69). Here's an example of converting var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });70 to boolean: var connection = mysql.createConnection('mysql://user:pass@host/db?debug=true&charset=BIG5_CHINESE_CI&timezone=-0700');9 WARNING: YOU MUST INVOKE the parser using one of these three field functions in your custom typeCast callback. They can only be called once. Debugging and reporting problemsIf you are running into problems, one thing that may help is enabling the $ npm install mysqljs/mysql11 mode for the connection: var connection = mysql.createConnection({ host : 'localhost', ssl : { ca : fs.readFileSync(__dirname + '/mysql-ca.crt') } });0 This will print all incoming and outgoing packets on stdout. You can also restrict debugging to packet types by passing an array of types to debug: var connection = mysql.createConnection({ host : 'localhost', ssl : { ca : fs.readFileSync(__dirname + '/mysql-ca.crt') } });1 to restrict debugging to the query and data packets. If that does not help, feel free to open a GitHub issue. A good GitHub issue will have:
Security issuesSecurity issues should not be first reported through GitHub or another public forum, but kept private in order for the collaborators to assess the report and either (a) devise a fix and plan a release date or (b) assert that it is not a security issue (in which case it can be posted in a public forum, like a GitHub issue). The primary private forum is email, either by emailing the module's author or opening a GitHub issue simply asking to whom a security issues should be addressed to without disclosing the issue or type of issue. An ideal report would include a clear indication of what the security issue is and how it would be exploited, ideally with an accompanying proof of concept ("PoC") for collaborators to work against and validate potentional fixes against. ContributingThis project welcomes contributions from the community. Contributions are accepted using GitHub pull requests. If you're not familiar with making GitHub pull requests, please refer to the GitHub documentation "Creating a pull request". For a good pull request, we ask you provide the following:
Running testsThe test suite is split into two parts: unit tests and integration tests. The unit tests run on any machine while the integration tests require a MySQL server instance to be setup. Running unit testsvar connection = mysql.createConnection({ host : 'localhost', ssl : { ca : fs.readFileSync(__dirname + '/mysql-ca.crt') } });2 Running integration testsSet the environment variables var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });76, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });77, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });78, var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });79 and var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });80. var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });81 can also be used in place of var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });77 and var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });78 to connect over a UNIX socket. Then run var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });84. For example, if you have an installation of mysql running on localhost:3306 and no password set for the var mysql = require('mysql'); var connection = mysql.createConnection({ host : 'example.org', user : 'bob', password : 'secret' }); connection.connect(function(err) { if (err) { console.error('error connecting: ' + err.stack); return; } console.log('connected as id ' + connection.threadId); });85 user, run: Bagaimana JavaScript dijalankan?Javascript cenderung sangat cepat karena dijalankan langsung di dalam browser. Selain itu, browser utama sebagian besar mendukung kompilasi JIT (Just In Time), yang berarti tidak perlu mengkompilasi code sebelum menjalankannya.
Bagaimana cara membuat komentar di JavaScript?Komentar multi line diawali dengan /* (garis miring bintang) dan diakhiri dengan */ (bintang garis miring). Kode atau teks apa pun yang berada diantara /* dan */ tidak akan dieksekusi oleh mesin.
JavaScript pakai aplikasi apa?Namun, sebelumnya Anda membutuhkan beberapa aplikasi berikut untuk mendukung Anda belajar Javascript: Web browser (Google Chrome, Firefox, atau lainnya). Teks editor (Atom, Notepad, atau lainnya). Web server, untuk menjalankan kode pemrograman.
JavaScript umumnya dipakai di mana?JavaScript digunakan pada web, aplikasi seluler, dan game development sehingga menjadi salah satu yang layak Anda pelajari.
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