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@sysini/mssql

v7.1.3

Published

Microsoft SQL Server client for Node.js.

Downloads

3

Readme

node-mssql

Microsoft SQL Server client for Node.js

[![NPM Version][npm-image]][npm-url] [![NPM Downloads][downloads-image]][downloads-url] [![Travis CI][travis-image]][travis-url] [![Appveyor CI][appveyor-image]][appveyor-url] Join the chat at https://gitter.im/patriksimek/node-mssql

Supported TDS drivers:

  • [Tedious][tedious-url] (pure JavaScript - Windows/macOS/Linux, default)
  • [Microsoft / Contributors Node V8 Driver for Node.js for SQL Server][msnodesqlv8-url] (v2 native - Windows or Linux/macOS 64 bits only)

Installation

npm install mssql

Short Example: Use Connect String

const sql = require('mssql')

async () => {
    try {
        // make sure that any items are correctly URL encoded in the connection string
        await sql.connect('Server=localhost,1433;Database=database;User Id=username;Password=password;Encrypt=true')
        const result = await sql.query`select * from mytable where id = ${value}`
        console.dir(result)
    } catch (err) {
        // ... error checks
    }
}

If you're on Windows Azure, add ?encrypt=true to your connection string. See docs to learn more.

Parts of the connection URI should be correctly URL encoded so that the URI can be parsed correctly.

Longer Example: Connect via Config Object

Assuming you have set the appropriate environment variables, you can construct a config object as follows:

const sql = require('mssql')
const sqlConfig = {
  user: process.env.DB_USER,
  password: process.env.DB_PWD,
  database: process.env.DB_NAME,
  server: 'localhost',
  pool: {
    max: 10,
    min: 0,
    idleTimeoutMillis: 30000
  },
  options: {
    encrypt: true, // for azure
    trustServerCertificate: false // change to true for local dev / self-signed certs
  }
}

async () => {
 try {
  // make sure that any items are correctly URL encoded in the connection string
  await sql.connect(sqlConfig)
  const result = await sql.query`select * from mytable where id = ${value}`
  console.dir(result)
 } catch (err) {
  // ... error checks
 }
}

Documentation

Examples

Configuration

Drivers

Connections

Requests

Transactions

Prepared Statements

Other

Examples

Config

const config = {
    user: '...',
    password: '...',
    server: 'localhost', // You can use 'localhost\\instance' to connect to named instance
    database: '...',
}

Async/Await

const sql = require('mssql')

(async function () {
    try {
        let pool = await sql.connect(config)
        let result1 = await pool.request()
            .input('input_parameter', sql.Int, value)
            .query('select * from mytable where id = @input_parameter')
            
        console.dir(result1)
    
        // Stored procedure
        
        let result2 = await pool.request()
            .input('input_parameter', sql.Int, value)
            .output('output_parameter', sql.VarChar(50))
            .execute('procedure_name')
        
        console.dir(result2)
    } catch (err) {
        // ... error checks
    }
})()

sql.on('error', err => {
    // ... error handler
})

Promises

Queries

const sql = require('mssql')

sql.on('error', err => {
    // ... error handler
})

sql.connect(config).then(pool => {
    // Query
    
    return pool.request()
        .input('input_parameter', sql.Int, value)
        .query('select * from mytable where id = @input_parameter')
}).then(result => {
    console.dir(result)
}).catch(err => {
  // ... error checks
});

Stored procedures

const sql = require('mssql')

sql.on('error', err => {
    // ... error handler
})

sql.connect(config).then(pool => {
    
    // Stored procedure
    
    return pool.request()
        .input('input_parameter', sql.Int, value)
        .output('output_parameter', sql.VarChar(50))
        .execute('procedure_name')
}).then(result => {
    console.dir(result)
}).catch(err => {
    // ... error checks
})

Native Promise is used by default. You can easily change this with sql.Promise = require('myownpromisepackage').

ES6 Tagged template literals

const sql = require('mssql')

sql.connect(config).then(() => {
    return sql.query`select * from mytable where id = ${value}`
}).then(result => {
    console.dir(result)
}).catch(err => {
    // ... error checks
})

sql.on('error', err => {
    // ... error handler
})

All values are automatically sanitized against sql injection. This is because it is rendered as prepared statement, and thus all limitations imposed in MS SQL on parameters apply. e.g. Column names cannot be passed/set in statements using variables.

Callbacks

const sql = require('mssql')

sql.connect(config, err => {
    // ... error checks

    // Query

    new sql.Request().query('select 1 as number', (err, result) => {
        // ... error checks

        console.dir(result)
    })

    // Stored Procedure

    new sql.Request()
    .input('input_parameter', sql.Int, value)
    .output('output_parameter', sql.VarChar(50))
    .execute('procedure_name', (err, result) => {
        // ... error checks

        console.dir(result)
    })

    // Using template literal

    const request = new sql.Request()
    request.query(request.template`select * from mytable where id = ${value}`, (err, result) => {
        // ... error checks
        console.dir(result)
    })
})

sql.on('error', err => {
    // ... error handler
})

Streaming

If you plan to work with large amount of rows, you should always use streaming. Once you enable this, you must listen for events to receive data.

const sql = require('mssql')

sql.connect(config, err => {
    // ... error checks

    const request = new sql.Request()
    request.stream = true // You can set streaming differently for each request
    request.query('select * from verylargetable') // or request.execute(procedure)

    request.on('recordset', columns => {
        // Emitted once for each recordset in a query
    })

    request.on('row', row => {
        // Emitted for each row in a recordset
    })

    request.on('rowsaffected', rowCount => {
        // Emitted for each `INSERT`, `UPDATE` or `DELETE` statement
        // Requires NOCOUNT to be OFF (default)
    })

    request.on('error', err => {
        // May be emitted multiple times
    })

    request.on('done', result => {
        // Always emitted as the last one
    })
})

sql.on('error', err => {
    // ... error handler
})

When streaming large sets of data you want to back-off or chunk the amount of data you're processing to prevent memory exhaustion issues; you can use the Request.pause() function to do this. Here is an example of managing rows in batches of 15:

let rowsToProcess = [];
request.on('row', row => {
  rowsToProcess.push(row);
  if (rowsToProcess.length >= 15) {
    request.pause();
    processRows();
  }
});
request.on('done', () => {
    processRows();
});

function processRows() {
  // process rows
  rowsToProcess = [];
  request.resume();
}

Pool Management

An important concept to understand when using this library is Connection Pooling as this library uses connection pooling extensively.

As one Node JS process is able to handle multiple requests at once, we can take advantage of this long running process to create a pool of database connections for reuse; this saves overhead of connecting to the database for each request (as would be the case in something like PHP, where one process handles one request).

With the advantages of pooling comes some added complexities, but these are mostly just conceptual and once you understand how the pooling is working, it is simple to make use of it efficiently and effectively.

The Global Connection (Pool)

To assist with pool management in your application there is the global connect() function that is available for use. As of v6 of this library a developer can make repeated calls to this function to obtain the global connection pool. This means you do not need to keep track of the pool in your application (as used to be the case). If the global pool is already connected, it will resolve to the connected pool. For example:

const sql = require('mssql')

// run a query against the global connection pool
function runQuery(query) {
  // sql.connect() will return the existing global pool if it exists or create a new one if it doesn't
  return sql.connect().then((pool) => {
    return pool.query(query)
  })
}

Here we obtain the global connection pool by running sql.connect() and we then run the query against the pool. We also do not close the pool after the query is executed and that is because other queries may need to be run against this pool and closing it will add an overhead to running the query. We should only ever close the pool when our application is finished. For example, if we are running some kind of CLI tool or a CRON job:

const sql = require('mssql')

(() => {
  sql.connect().then(pool => {
    return pool.query('SELECT 1')
  }).then(result => {
    // do something with result
  }).then(() => {
    return sql.close()
  })
})()

Here the connection will be closed and the node process will exit once the queries and other application logic has completed. You should aim to only close the pool once in your application, when it is exiting or you know your application will never make another SQL query.

Advanced Pool Management

In some instances you will not want to use the connection pool, you may have multiple databases to connect to or you may have one pool for read-only operations and another pool for read-write. In this instance you will need to implement your own pool management.

That could look something like this:

const { ConnectionPool } = require('mssql')
const POOLS = {}

function createPool(config, name) {
  if (getPool(name)) {
    return Promise.reject(new Error('Pool with this name already exists'))
  }
  return (new ConnectionPool(config)).connect().then((pool) => {
    return POOLS[name] = pool
  })
}

function closePool(name) {
  const pool = getPool(name)
  if (pool) {
    delete POOLS[name]
    return pool.close()
  }
  return Promise.resolve()
}

function getPool(name) {
  if (Object.prototype.hasOwnProperty.apply(POOLS, name)) {
    return POOLS[name]
  }
}

module.exports = {
  closePool,
  createPool,
  getPool
}

This helper file can then be used in your application to create, fetch and close your pools. As with the global pools, you should aim to only close a pool when you know it will never be needed by the application again; typically this will be when your application is shutting down.

Connection Pools

Using a single connection pool for your application/service is recommended. Instantiating a pool with a callback, or immediately calling .connect, is asynchronous to ensure a connection can be established before returning. From that point, you're able to acquire connections as normal:

const sql = require('mssql')

// async/await style:
const pool1 = new sql.ConnectionPool(config);
const pool1Connect = pool1.connect();

pool1.on('error', err => {
    // ... error handler
})

async function messageHandler() {
    await pool1Connect; // ensures that the pool has been created
    try {
        const request = pool1.request(); // or: new sql.Request(pool1)
        const result = await request.query('select 1 as number')
        console.dir(result)
        return result;
    } catch (err) {
        console.error('SQL error', err);
    }
}

// promise style:
const pool2 = new sql.ConnectionPool(config)
const pool2Connect = pool2.connect()

pool2.on('error', err => {
    // ... error handler
})

function runStoredProcedure() {
    return pool2Connect.then((pool) => {
        pool.request() // or: new sql.Request(pool2)
        .input('input_parameter', sql.Int, 10)
        .output('output_parameter', sql.VarChar(50))
        .execute('procedure_name', (err, result) => {
            // ... error checks
            console.dir(result)
        })
    }).catch(err => {
        // ... error handler
    })
}

Awaiting or .thening the pool creation is a safe way to ensure that the pool is always ready, without knowing where it is needed first. In practice, once the pool is created then there will be no delay for the next operation.

As of v6.1.0 you can make repeat calls to ConnectionPool.connect() and ConnectonPool.close() without an error being thrown, allowing for the safe use of mssql.connect().then(...) throughout your code as well as making multiple calls to close when your application is shutting down.

The ability to call connect() repeatedly is intended to make pool management easier, however it is still recommended to follow the example above where connect() is called once and using the original resolved connection promise. Repeatedly calling connect() when running queries risks running into problems when close() is called on the pool.

ES6 Tagged template literals

new sql.ConnectionPool(config).connect().then(pool => {
    return pool.query`select * from mytable where id = ${value}`
}).then(result => {
    console.dir(result)
}).catch(err => {
    // ... error checks
})

All values are automatically sanitized against sql injection.

Managing connection pools

Most applications will only need a single ConnectionPool that can be shared throughout the code. To aid the sharing of a single pool this library exposes a set of functions to access a single global connection. eg:

// as part of your application's boot process

const sql = require('mssql')
const poolPromise = sql.connect()

// during your applications runtime

poolPromise.then(() => {
  return sql.query('SELECT 1')
}).then(result => {
  console.dir(result)
})

// when your application exits
poolPromise.then(() => {
  return sql.close()
})

If you require multiple pools per application (perhaps you have many DBs you need to connect to or you want a read-only pool), then you will need to manage your pools yourself. The best way to do this is to create a shared library file that can hold references to the pools for you. For example:

const sql = require('mssql')

const pools = {}

// manage a set of pools by name (config will be required to create the pool)
// a pool will be removed when it is closed
async function getPool(name, config) {
  if (!Object.prototype.hasOwnProperty.call(pools, name)) {
    const pool = new sql.ConnectionPool(config)
    const close = pool.close.bind(pool)
    pool.close = (...args) => {
      delete pools[name]
      return close(...args)
    }
    await pool.connect()
    pools[name] = pool
  }
  return pools[name]
}

// close all pools
function closeAll() {
  return Promise.all(Object.values(pools).map((pool) => {
    return pool.close()
  }))
}

module.exports = {
  closeAll,
  getPool
}

You can then use this library file in your code to get a connected pool when you need it:

const { getPool } = require('./path/to/file')

// run a query
async function runQuery(query, config) {
  // pool will always be connected when the promise has resolved - may reject if the connection config is invalid
  const pool = await getPool('default', config)
  const result = await pool.request().query(query)
  return result
}

Configuration

const config = {
    user: '...',
    password: '...',
    server: 'localhost',
    database: '...',
    pool: {
        max: 10,
        min: 0,
        idleTimeoutMillis: 30000
    }
}

General (same for all drivers)

  • user - User name to use for authentication.
  • password - Password to use for authentication.
  • server - Server to connect to. You can use 'localhost\instance' to connect to named instance.
  • port - Port to connect to (default: 1433). Don't set when connecting to named instance.
  • domain - Once you set domain, driver will connect to SQL Server using domain login.
  • database - Database to connect to (default: dependent on server configuration).
  • connectionTimeout - Connection timeout in ms (default: 15000).
  • requestTimeout - Request timeout in ms (default: 15000). NOTE: msnodesqlv8 driver doesn't support timeouts < 1 second. When passed via connection string, the key must be request timeout
  • stream - Stream recordsets/rows instead of returning them all at once as an argument of callback (default: false). You can also enable streaming for each request independently (request.stream = true). Always set to true if you plan to work with large amount of rows.
  • parseJSON - Parse JSON recordsets to JS objects (default: false). For more information please see section JSON support.
  • pool.max - The maximum number of connections there can be in the pool (default: 10).
  • pool.min - The minimum of connections there can be in the pool (default: 0).
  • pool.idleTimeoutMillis - The Number of milliseconds before closing an unused connection (default: 30000).
  • arrayRowMode - Return row results as a an array instead of a keyed object. Also adds columns array. See Handling Duplicate Column Names

Complete list of pool options can be found here.

Formats

In addition to configuration object there is an option to pass config as a connection string. Connection strings are supported.

Classic Connection String
Server=localhost,1433;Database=database;User Id=username;Password=password;Encrypt=true
Driver=msnodesqlv8;Server=(local)\INSTANCE;Database=database;UID=DOMAIN\username;PWD=password;Encrypt=true

Drivers

Tedious

Default driver, actively maintained and production ready. Platform independent, runs everywhere Node.js runs. Officially supported by Microsoft.

Extra options:

  • beforeConnect(conn) - Function, which is invoked before opening the connection. The parameter conn is the configured tedious Connection. It can be used for attaching event handlers like in this example:
require('mssql').connect({...config, beforeConnect: conn => {
  conn.once('connect', err => { err ? console.error(err) : console.log('mssql connected')})
  conn.once('end', err => { err ? console.error(err) : console.log('mssql disconnected')})
}})
  • options.instanceName - The instance name to connect to. The SQL Server Browser service must be running on the database server, and UDP port 1434 on the database server must be reachable.
  • options.useUTC - A boolean determining whether or not use UTC time for values without time zone offset (default: true).
  • options.encrypt - A boolean determining whether or not the connection will be encrypted (default: true).
  • options.tdsVersion - The version of TDS to use (default: 7_4, available: 7_1, 7_2, 7_3_A, 7_3_B, 7_4).
  • options.appName - Application name used for SQL server logging.
  • options.abortTransactionOnError - A boolean determining whether to rollback a transaction automatically if any error is encountered during the given transaction's execution. This sets the value for XACT_ABORT during the initial SQL phase of a connection.

Authentication:

On top of the extra options, an authentication property can be added to the pool config option

  • authentication - An object with authentication settings, according to the Tedious Documentation. Passing this object will override user, password, domain settings.
  • authentication.type - Type of the authentication method, valid types are default, ntlm, azure-active-directory-password, azure-active-directory-access-token, azure-active-directory-msi-vm, or azure-active-directory-msi-app-service
  • authentication.options - Options of the authentication required by the tedious driver, depends on authentication.type. For more details, check Tedious Authentication Interfaces

More information about Tedious specific options: http://tediousjs.github.io/tedious/api-connection.html

Microsoft / Contributors Node V8 Driver for Node.js for SQL Server

Requires Node.js v10+ or newer. Windows 32-64 bits or Linux/macOS 64 bits only. This driver is not part of the default package and must be installed separately by npm install msnodesqlv8@^2. To use this driver, use this require syntax: const sql = require('mssql/msnodesqlv8').

Note: If you use import into your lib to prepare your request (const { VarChar } = require('mssql')) you also need to upgrade all your types import into your code (const { VarChar } = require('mssql/msnodesqlv8')) or a connection.on is not a function error will be thrown.

Extra options:

  • beforeConnect(conn) - Function, which is invoked before opening the connection. The parameter conn is the connection configuration, that can be modified to pass extra parameters to the driver's open() method.
  • connectionString - Connection string (default: see below).
  • options.instanceName - The instance name to connect to. The SQL Server Browser service must be running on the database server, and UDP port 1444 on the database server must be reachable.
  • options.trustedConnection - Use Windows Authentication (default: false).
  • options.useUTC - A boolean determining whether or not to use UTC time for values without time zone offset (default: true).

Default connection string when connecting to port:

Driver={SQL Server Native Client 11.0};Server={#{server},#{port}};Database={#{database}};Uid={#{user}};Pwd={#{password}};Trusted_Connection={#{trusted}};

Default connection string when connecting to named instance:

Driver={SQL Server Native Client 11.0};Server={#{server}\\#{instance}};Database={#{database}};Uid={#{user}};Pwd={#{password}};Trusted_Connection={#{trusted}};

Please note that the connection string with this driver is not the same than tedious and use yes/no instead of true/false. You can see more on the ODBC documentation.

Connections

Internally, each ConnectionPool instance is a separate pool of TDS connections. Once you create a new Request/Transaction/Prepared Statement, a new TDS connection is acquired from the pool and reserved for desired action. Once the action is complete, connection is released back to the pool. Connection health check is built-in so once the dead connection is discovered, it is immediately replaced with a new one.

IMPORTANT: Always attach an error listener to created connection. Whenever something goes wrong with the connection it will emit an error and if there is no listener it will crash your application with an uncaught error.

const pool = new sql.ConnectionPool({ /* config */ })

Events

  • error(err) - Dispatched on connection error.

connect ([callback])

Create a new connection pool. The initial probe connection is created to find out whether the configuration is valid.

Arguments

  • callback(err) - A callback which is called after initial probe connection has established, or an error has occurred. Optional. If omitted, returns Promise.

Example

const pool = new sql.ConnectionPool({
    user: '...',
    password: '...',
    server: 'localhost',
    database: '...'
})

pool.connect(err => {
    // ...
})

Errors

  • ELOGIN (ConnectionError) - Login failed.
  • ETIMEOUT (ConnectionError) - Connection timeout.
  • EALREADYCONNECTED (ConnectionError) - Database is already connected!
  • EALREADYCONNECTING (ConnectionError) - Already connecting to database!
  • EINSTLOOKUP (ConnectionError) - Instance lookup failed.
  • ESOCKET (ConnectionError) - Socket error.

close()

Close all active connections in the pool.

Example

pool.close()

Request

const request = new sql.Request(/* [pool or transaction] */)

If you omit pool/transaction argument, global pool is used instead.

Events

  • recordset(columns) - Dispatched when metadata for new recordset are parsed.
  • row(row) - Dispatched when new row is parsed.
  • done(returnValue) - Dispatched when request is complete.
  • error(err) - Dispatched on error.
  • info(message) - Dispatched on informational message.

execute (procedure, [callback])

Call a stored procedure.

Arguments

  • procedure - Name of the stored procedure to be executed.
  • callback(err, recordsets, returnValue) - A callback which is called after execution has completed, or an error has occurred. returnValue is also accessible as property of recordsets. Optional. If omitted, returns Promise.

Example

const request = new sql.Request()
request.input('input_parameter', sql.Int, value)
request.output('output_parameter', sql.Int)
request.execute('procedure_name', (err, result) => {
    // ... error checks

    console.log(result.recordsets.length) // count of recordsets returned by the procedure
    console.log(result.recordsets[0].length) // count of rows contained in first recordset
    console.log(result.recordset) // first recordset from result.recordsets
    console.log(result.returnValue) // procedure return value
    console.log(result.output) // key/value collection of output values
    console.log(result.rowsAffected) // array of numbers, each number represents the number of rows affected by executed statemens

    // ...
})

Errors

  • EREQUEST (RequestError) - Message from SQL Server
  • ECANCEL (RequestError) - Cancelled.
  • ETIMEOUT (RequestError) - Request timeout.
  • ENOCONN (RequestError) - No connection is specified for that request.
  • ENOTOPEN (ConnectionError) - Connection not yet open.
  • ECONNCLOSED (ConnectionError) - Connection is closed.
  • ENOTBEGUN (TransactionError) - Transaction has not begun.
  • EABORT (TransactionError) - Transaction was aborted (by user or because of an error).

input (name, [type], value)

Add an input parameter to the request.

Arguments

  • name - Name of the input parameter without @ char.
  • type - SQL data type of input parameter. If you omit type, module automatically decide which SQL data type should be used based on JS data type.
  • value - Input parameter value. undefined and NaN values are automatically converted to null values.

Example

request.input('input_parameter', value)
request.input('input_parameter', sql.Int, value)

JS Data Type To SQL Data Type Map

  • String -> sql.NVarChar
  • Number -> sql.Int
  • Boolean -> sql.Bit
  • Date -> sql.DateTime
  • Buffer -> sql.VarBinary
  • sql.Table -> sql.TVP

Default data type for unknown object is sql.NVarChar.

You can define your own type map.

sql.map.register(MyClass, sql.Text)

You can also overwrite the default type map.

sql.map.register(Number, sql.BigInt)

Errors (synchronous)

  • EARGS (RequestError) - Invalid number of arguments.
  • EINJECT (RequestError) - SQL injection warning.

NB: Do not use parameters @p{n} as these are used by the internal drivers and cause a conflict.

output (name, type, [value])

Add an output parameter to the request.

Arguments

  • name - Name of the output parameter without @ char.
  • type - SQL data type of output parameter.
  • value - Output parameter value initial value. undefined and NaN values are automatically converted to null values. Optional.

Example

request.output('output_parameter', sql.Int)
request.output('output_parameter', sql.VarChar(50), 'abc')

Errors (synchronous)

  • EARGS (RequestError) - Invalid number of arguments.
  • EINJECT (RequestError) - SQL injection warning.

toReadableStream

Convert request to a Node.js ReadableStream

Example

const { pipeline } = require('stream')
const request = new sql.Request()
const readableStream = request.toReadableStream()
pipeline(readableStream, transformStream, writableStream)
request.query('select * from mytable')

OR if you wanted to increase the highWaterMark of the read stream to buffer more rows in memory

const { pipeline } = require('stream')
const request = new sql.Request()
const readableStream = request.toReadableStream({ highWaterMark: 100 })
pipeline(readableStream, transformStream, writableStream)
request.query('select * from mytable')

pipe (stream)

Sets request to stream mode and pulls all rows from all recordsets to a given stream.

Arguments

  • stream - Writable stream in object mode.

Example

const request = new sql.Request()
request.pipe(stream)
request.query('select * from mytable')
stream.on('error', err => {
    // ...
})
stream.on('finish', () => {
    // ...
})

query (command, [callback])

Execute the SQL command. To execute commands like create procedure or if you plan to work with local temporary tables, use batch instead.

Arguments

  • command - T-SQL command to be executed.
  • callback(err, recordset) - A callback which is called after execution has completed, or an error has occurred. Optional. If omitted, returns Promise.

Example

const request = new sql.Request()
request.query('select 1 as number', (err, result) => {
    // ... error checks

    console.log(result.recordset[0].number) // return 1

    // ...
})

Errors

  • ETIMEOUT (RequestError) - Request timeout.
  • EREQUEST (RequestError) - Message from SQL Server
  • ECANCEL (RequestError) - Cancelled.
  • ENOCONN (RequestError) - No connection is specified for that request.
  • ENOTOPEN (ConnectionError) - Connection not yet open.
  • ECONNCLOSED (ConnectionError) - Connection is closed.
  • ENOTBEGUN (TransactionError) - Transaction has not begun.
  • EABORT (TransactionError) - Transaction was aborted (by user or because of an error).
const request = new sql.Request()
request.query('select 1 as number; select 2 as number', (err, result) => {
    // ... error checks

    console.log(result.recordset[0].number) // return 1
    console.log(result.recordsets[0][0].number) // return 1
    console.log(result.recordsets[1][0].number) // return 2
})

NOTE: To get number of rows affected by the statement(s), see section Affected Rows.


batch (batch, [callback])

Execute the SQL command. Unlike query, it doesn't use sp_executesql, so is not likely that SQL Server will reuse the execution plan it generates for the SQL. Use this only in special cases, for example when you need to execute commands like create procedure which can't be executed with query or if you're executing statements longer than 4000 chars on SQL Server 2000. Also you should use this if you're plan to work with local temporary tables (more information here).

NOTE: Table-Valued Parameter (TVP) is not supported in batch.

Arguments

  • batch - T-SQL command to be executed.
  • callback(err, recordset) - A callback which is called after execution has completed, or an error has occurred. Optional. If omitted, returns Promise.

Example

const request = new sql.Request()
request.batch('create procedure #temporary as select * from table', (err, result) => {
    // ... error checks
})

Errors

  • ETIMEOUT (RequestError) - Request timeout.
  • EREQUEST (RequestError) - Message from SQL Server
  • ECANCEL (RequestError) - Cancelled.
  • ENOCONN (RequestError) - No connection is specified for that request.
  • ENOTOPEN (ConnectionError) - Connection not yet open.
  • ECONNCLOSED (ConnectionError) - Connection is closed.
  • ENOTBEGUN (TransactionError) - Transaction has not begun.
  • EABORT (TransactionError) - Transaction was aborted (by user or because of an error).

You can enable multiple recordsets in queries with the request.multiple = true command.


bulk (table, [options,] [callback])

Perform a bulk insert.

Arguments

  • table - sql.Table instance.
  • options - Options object to be passed through to driver (currently tedious only). Optional. If argument is a function it will be treated as the callback.
  • callback(err, rowCount) - A callback which is called after bulk insert has completed, or an error has occurred. Optional. If omitted, returns Promise.

Example

const table = new sql.Table('table_name') // or temporary table, e.g. #temptable
table.create = true
table.columns.add('a', sql.Int, {nullable: true, primary: true})
table.columns.add('b', sql.VarChar(50), {nullable: false})
table.rows.add(777, 'test')

const request = new sql.Request()
request.bulk(table, (err, result) => {
    // ... error checks
})

IMPORTANT: Always indicate whether the column is nullable or not!

TIP: If you set table.create to true, module will check if the table exists before it start sending data. If it doesn't, it will automatically create it. You can specify primary key columns by setting primary: true to column's options. Primary key constraint on multiple columns is supported.

TIP: You can also create Table variable from any recordset with recordset.toTable(). You can optionally specify table type name in the first argument.

Errors

  • ENAME (RequestError) - Table name must be specified for bulk insert.
  • ETIMEOUT (RequestError) - Request timeout.
  • EREQUEST (RequestError) - Message from SQL Server
  • ECANCEL (RequestError) - Cancelled.
  • ENOCONN (RequestError) - No connection is specified for that request.
  • ENOTOPEN (ConnectionError) - Connection not yet open.
  • ECONNCLOSED (ConnectionError) - Connection is closed.
  • ENOTBEGUN (TransactionError) - Transaction has not begun.
  • EABORT (TransactionError) - Transaction was aborted (by user or because of an error).

cancel()

Cancel currently executing request. Return true if cancellation packet was send successfully.

Example

const request = new sql.Request()
request.query('waitfor delay \'00:00:05\'; select 1 as number', (err, result) => {
    console.log(err instanceof sql.RequestError)  // true
    console.log(err.message)                      // Cancelled.
    console.log(err.code)                         // ECANCEL

    // ...
})

request.cancel()

Transaction

IMPORTANT: always use Transaction class to create transactions - it ensures that all your requests are executed on one connection. Once you call begin, a single connection is acquired from the connection pool and all subsequent requests (initialized with the Transaction object) are executed exclusively on this connection. After you call commit or rollback, connection is then released back to the connection pool.

const transaction = new sql.Transaction(/* [pool] */)

If you omit connection argument, global connection is used instead.

Example

const transaction = new sql.Transaction(/* [pool] */)
transaction.begin(err => {
    // ... error checks

    const request = new sql.Request(transaction)
    request.query('insert into mytable (mycolumn) values (12345)', (err, result) => {
        // ... error checks

        transaction.commit(err => {
            // ... error checks

            console.log("Transaction committed.")
        })
    })
})

Transaction can also be created by const transaction = pool.transaction(). Requests can also be created by const request = transaction.request().

Aborted transactions

This example shows how you should correctly handle transaction errors when abortTransactionOnError (XACT_ABORT) is enabled. Added in 2.0.

const transaction = new sql.Transaction(/* [pool] */)
transaction.begin(err => {
    // ... error checks

    let rolledBack = false

    transaction.on('rollback', aborted => {
        // emited with aborted === true

        rolledBack = true
    })

    new sql.Request(transaction)
    .query('insert into mytable (bitcolumn) values (2)', (err, result) => {
        // insert should fail because of invalid value

        if (err) {
            if (!rolledBack) {
                transaction.rollback(err => {
                    // ... error checks
                })
            }
        } else {
            transaction.commit(err => {
                // ... error checks
            })
        }
    })
})

Events

  • begin - Dispatched when transaction begin.
  • commit - Dispatched on successful commit.
  • rollback(aborted) - Dispatched on successful rollback with an argument determining if the transaction was aborted (by user or because of an error).

begin ([isolationLevel], [callback])

Begin a transaction.

Arguments

  • isolationLevel - Controls the locking and row versioning behavior of TSQL statements issued by a connection. Optional. READ_COMMITTED by default. For possible values see sql.ISOLATION_LEVEL.
  • callback(err) - A callback which is called after transaction has began, or an error has occurred. Optional. If omitted, returns Promise.

Example

const transaction = new sql.Transaction()
transaction.begin(err => {
    // ... error checks
})

Errors

  • ENOTOPEN (ConnectionError) - Connection not yet open.
  • EALREADYBEGUN (TransactionError) - Transaction has already begun.

commit ([callback])

Commit a transaction.

Arguments

  • callback(err) - A callback which is called after transaction has committed, or an error has occurred. Optional. If omitted, returns Promise.

Example

const transaction = new sql.Transaction()
transaction.begin(err => {
    // ... error checks

    transaction.commit(err => {
        // ... error checks
    })
})

Errors

  • ENOTBEGUN (TransactionError) - Transaction has not begun.
  • EREQINPROG (TransactionError) - Can't commit transaction. There is a request in progress.

rollback ([callback])

Rollback a transaction. If the queue isn't empty, all queued requests will be Cancelled and the transaction will be marked as aborted.

Arguments

  • callback(err) - A callback which is called after transaction has rolled back, or an error has occurred. Optional. If omitted, returns Promise.

Example

const transaction = new sql.Transaction()
transaction.begin(err => {
    // ... error checks

    transaction.rollback(err => {
        // ... error checks
    })
})

Errors

  • ENOTBEGUN (TransactionError) - Transaction has not begun.
  • EREQINPROG (TransactionError) - Can't rollback transaction. There is a request in progress.

Prepared Statement

IMPORTANT: always use PreparedStatement class to create prepared statements - it ensures that all your executions of prepared statement are executed on one connection. Once you call prepare, a single connection is acquired from the connection pool and all subsequent executions are executed exclusively on this connection. After you call unprepare, the connection is then released back to the connection pool.

const ps = new sql.PreparedStatement(/* [pool] */)

If you omit the connection argument, the global connection is used instead.

Example

const ps = new sql.PreparedStatement(/* [pool] */)
ps.input('param', sql.Int)
ps.prepare('select @param as value', err => {
    // ... error checks

    ps.execute({param: 12345}, (err, result) => {
        // ... error checks

        // release the connection after queries are executed
        ps.unprepare(err => {
            // ... error checks

        })
    })
})

IMPORTANT: Remember that each prepared statement means one reserved connection from the pool. Don't forget to unprepare a prepared statement when you've finished your queries!

You can execute multiple queries against the same prepared statement but you must unprepare the statement when you have finished using it otherwise you will cause the connection pool to run out of available connections.

TIP: You can also create prepared statements in transactions (new sql.PreparedStatement(transaction)), but keep in mind you can't execute other requests in the transaction until you call unprepare.


input (name, type)

Add an input parameter to the prepared statement.

Arguments

  • name - Name of the input parameter without @ char.
  • type - SQL data type of input parameter.

Example

ps.input('input_parameter', sql.Int)
ps.input('input_parameter', sql.VarChar(50))

Errors (synchronous)

  • EARGS (PreparedStatementError) - Invalid number of arguments.
  • EINJECT (PreparedStatementError) - SQL injection warning.

output (name, type)

Add an output parameter to the prepared statement.

Arguments

  • name - Name of the output parameter without @ char.
  • type - SQL data type of output parameter.

Example

ps.output('output_parameter', sql.Int)
ps.output('output_parameter', sql.VarChar(50))

Errors (synchronous)

  • EARGS (PreparedStatementError) - Invalid number of arguments.
  • EINJECT (PreparedStatementError) - SQL injection warning.

prepare (statement, [callback])

Prepare a statement.

Arguments

  • statement - T-SQL statement to prepare.
  • callback(err) - A callback which is called after preparation has completed, or an error has occurred. Optional. If omitted, returns Promise.

Example

const ps = new sql.PreparedStatement()
ps.prepare('select @param as value', err => {
    // ... error checks
})

Errors

  • ENOTOPEN (ConnectionError) - Connection not yet open.
  • EALREADYPREPARED (PreparedStatementError) - Statement is already prepared.
  • ENOTBEGUN (TransactionError) - Transaction has not begun.

execute (values, [callback])

Execute a prepared statement.

Arguments

  • values - An object whose names correspond to the names of parameters that were added to the prepared statement before it was prepared.
  • callback(err) - A callback which is called after execution has completed, or an error has occurred. Optional. If omitted, returns Promise.

Example

const ps = new sql.PreparedStatement()
ps.input('param', sql.Int)
ps.prepare('select @param as value', err => {
    // ... error checks

    ps.execute({param: 12345}, (err, result) => {
        // ... error checks

        console.log(result.recordset[0].value) // return 12345
        console.log(result.rowsAffected) // Returns number of affected rows in case of INSERT, UPDATE or DELETE statement.
        
        ps.unprepare(err => {
            // ... error checks
        })
    })
})

You can also stream executed request.

const ps = new sql.PreparedStatement()
ps.input('param', sql.Int)
ps.prepare('select @param as value', err => {
    // ... error checks

    ps.stream = true
    const request = ps.execute({param: 12345})

    request.on('recordset', columns => {
        // Emitted once for each recordset in a query
    })

    request.on('row', row => {
        // Emitted for each row in a recordset
    })

    request.on('error', err => {
        // May be emitted multiple times
    })

    request.on('done', result => {
        // Always emitted as the last one
        
        console.log(result.rowsAffected) // Returns number of affected rows in case of INSERT, UPDATE or DELETE statement.
        
        ps.unprepare(err => {
            // ... error checks
        })
    })
})

TIP: To learn more about how number of affected rows works, see section Affected Rows.

Errors

  • ENOTPREPARED (PreparedStatementError) - Statement is not prepared.
  • ETIMEOUT (RequestError) - Request timeout.
  • EREQUEST (RequestError) - Message from SQL Server
  • ECANCEL (RequestError) - Cancelled.

unprepare ([callback])

Unprepare a prepared statement.

Arguments

  • callback(err) - A callback which is called after unpreparation has completed, or an error has occurred. Optional. If omitted, returns Promise.

Example

const ps = new sql.PreparedStatement()
ps.input('param', sql.Int)
ps.prepare('select @param as value', err => {
    // ... error checks

    ps.unprepare(err => {
        // ... error checks

    })
})

Errors

  • ENOTPREPARED (PreparedStatementError) - Statement is not prepared.

CLI

Before you can start using CLI, you must install mssql globally with npm install mssql -g. Once you do that you will be able to execute mssql command.

Setup

Create a .mssql.json configuration file (anywhere). Structure of the file is the same as the standard configuration object.

{
    "user": "...",
    "password": "...",
    "server": "localhost",
    "database": "..."
}

Example

echo "select * from mytable" | mssql /path/to/config

Results in:

[[{"username":"patriksimek","password":"tooeasy"}]]

You can also query for multiple recordsets.

echo "select * from mytable; select * from myothertable" | mssql

Results in:

[[{"username":"patriksimek","password":"tooeasy"}],[{"id":15,"name":"Product name"}]]

If you omit config path argument, mssql will try to load it from current working directory.

Geography and Geometry

node-mssql has built-in serializer for Geography and Geometry CLR data types.

select geography::STGeomFromText('LINESTRING(-122.360 47.656, -122.343 47.656 )', 4326)
select geometry::STGeomFromText('LINESTRING (100 100 10.3 12, 20 180, 180 180)', 0)

Results in:

{ srid: 4326,
  version: 1,
  points: [ { x: 47.656, y: -122.36 }, { x: 47.656, y: -122.343 } ],
  figures: [ { attribute: 1, pointOffset: 0 } ],
  shapes: [ { parentOffset: -1, figureOffset: 0, type: 2 } ],
  segments: [] }

{ srid: 0,
  version: 1,
  points:
   [ { x: 100, y: 100, z: 10.3, m: 12 },
     { x: 20, y: 180, z: NaN, m: NaN },
     { x: 180, y: 180, z: NaN, m: NaN } ],
  figures: [ { attribute: 1, pointOffset: 0 } ],
  shapes: [ { parentOffset: -1, figureOffset: 0, type: 2 } ],
  segments: [] }

Table-Valued Parameter (TVP)

Supported on SQL Server 2008 and later. You can pass a data table as a parameter to stored procedure. First, we have to create custom type in our database.

CREATE TYPE TestType AS TABLE ( a VARCHAR(50), b INT );

Next we will need a stored procedure.

CREATE PROCEDURE MyCustomStoredProcedure (@tvp TestType readonly) AS SELECT * FROM @tvp

Now let's go back to our Node.js app.

const tvp = new sql.Table() // You can optionally specify table type name in the first argument.

// Columns must correspond with type we have created in database.
tvp.columns.add('a', sql.VarChar(50))
tvp.columns.add('b', sql.Int)

// Add rows
tvp.rows.add('hello tvp', 777) // Values are in same order as columns.

You can send table as a parameter to stored procedure.

const request = new sql.Request()
request.input('tvp', tvp)
request.execute('MyCustomStoredProcedure', (err, result) => {
    // ... error checks

    console.dir(result.recordsets[0][0]) // {a: 'hello tvp', b: 777}
})

TIP: You can also create Table variable from any recordset with recordset.toTable(). You can optionally specify table type name in the first argument.

Response Schema

An object returned from a sucessful basic query would look like the following.

{
	recordsets: [
		[
			{
				COL1: "some content",
				COL2: "some more content"
			}
		]
	],
	recordset: [
		{
			COL1: "some content",
			COL2: "some more content"
		}
	],
	output: {},
	rowsAffected: [1]
}

Affected Rows

If you're performing INSERT, UPDATE or DELETE in a query, you can read number of affected rows. The rowsAffected variable is an array of numbers. Each number represents number of affected rows by a single statement.

Example using Promises

const request = new sql.Request()
request.query('update myAwesomeTable set awesomness = 100').then(result => {
    console.log(result.rowsAffected)
})

Example using callbacks

const request = new sql.Request()
request.query('update myAwesomeTable set awesomness = 100', (err, result) => {
    console.log(result.rowsAffected)
})

Example using streaming

In addition to the rowsAffected attribute on the done event, each statement will emit the number of affected rows as it is completed.

const request = new sql.Request()
request.stream = true
request.query('update myAwesomeTable set awesomness = 100')
request.on('rowsaffected', rowCount => {
    console.log(rowCount)
})
request.on('done', result => {
    console.log(result.rowsAffected)
})

JSON support

SQL Server 2016 introduced built-in JSON serialization. By default, JSON is returned as a plain text in a special column named JSON_F52E2B61-18A1-11d1-B105-00805F49916B.

Example

SELECT
    1 AS 'a.b.c',
    2 AS 'a.b.d',
    3 AS 'a.x',
    4 AS 'a.y'
FOR JSON PATH

Results in:

recordset = [ { 'JSON_F52E2B61-18A1-11d1-B105-00805F49916B': '{"a":{"b":{"c":1,"d":2},"x":3,"y":4}}' } ]

You can enable built-in JSON parser with config.parseJSON = true. Once you enable this, recordset will contain rows of parsed JS objects. Given the same example, result will look like this:

recordset = [ { a: { b: { c: 1, d: 2 }, x: 3, y: 4 } } ]

IMPORTANT: In order for this to work, there must be exactly one column named JSON_F52E2B61-18A1-11d1-B105-00805F49916B in the recordset.

More information about JSON support can be found in official documentation.

Handling Duplicate Column Names

If your queries contain output columns with identical names, the default behaviour of mssql will only return column metadata for the last column with that name. You will also not always be able to re-assemble the order of output columns requested.

Default behaviour:

const request = new sql.Request()
request
    .query("select 'asdf' as name, 'qwerty' as other_name, 'jkl' as name")
    .then(result => {
        console.log(result)
    });

Results in:

{
  recordsets: [
    [ { name: [ 'asdf', 'jkl' ], other_name: 'qwerty' } ]
  ],
  recordset: [ { name: [ 'asdf', 'jkl' ], other_name: 'qwerty' } ],
  output: {},
  rowsAffected: [ 1 ]
}

You can use the arrayRowMode configuration parameter to return the row values as arrays and add a separate array of column values. arrayRowMode can be set globally during the initial connection, or per-request.

const request = new sql.Request()
request.arrayRowMode = true
request
    .query("select 'asdf' as name, 'qwerty' as other_name, 'jkl' as name")
    .then(result => {
        console.log(result)
    });

Results in:

{
  recordsets: [ [ [ 'asdf', 'qwerty', 'jkl' ] ] ],
  recordset: [ [ 'asdf', 'qwerty', 'jkl' ] ],
  output: {},
  rowsAffected: [ 1 ],
  columns: [
    [
      {
        index: 0,
        name: 'name',
        length: 4,
        type: [sql.VarChar],
        scale: undefined,
        precision: undefined,
        nullable: false,
        caseSensitive: false,
        identity: false,
        readOnly: true
      },
      {
        index: 1,
        name: 'other_name',
        length: 6,
        type: [sql.VarChar],
        scale: undefined,
        precision: undefined,
        nullable: false,
        caseSensitive: false,
        identity: false,
        readOnly: true
      },
      {
        index: 2,
        name: 'name',
        length: 3,
        type: [sql.VarChar],
        scale: undefined,
        precision: undefined,
        nullable: false,
        caseSensitive: false,
        identity: false,
        readOnly: true
      }
    ]
  ]
}

Streaming Duplicate Column Names

When using arrayRowMode with stream enabled, the output from the recordset event (as described in Streaming) is returned as an array of column metadata, instead of as a keyed object. The order of the column metadata provided by the recordset event will match the order of row values when arrayRowMode is enabled.

Default behaviour (without arrayRowMode):

const request = new sql.Request()
request.stream = true
request.query("select 'asdf' as name, 'qwerty' as other_name, 'jkl' as name")
request.on('recordset', recordset => console.log(recordset))

Results in:

{
  name: {
    index: 2,
    name: 'name',
    length: 3,
    type: [sql.VarChar],
    scale: undefined,
    precision: undefined,
    nullable: false,
    caseSensitive: false,
    identity: false,
    readOnly: true
  },
  other_name: {
    index: 1,
    name: 'other_name',
    length: 6,
    type: [sql.VarChar],
    scale: undefined,
    precision: undefined,
    nullable: false,
    caseSensitive: false,
    identity: false,
    readOnly: true
  }
}

With arrayRowMode:

const request = new sql.Request()
request.stream = true
request.arrayRowMode = true
request.query("select 'asdf' as name, 'qwerty' as other_name, 'jkl' as name")

request.on('recordset', recordset => console.log(recordset))

Results in:

[
  {
    index: 0,
    name: 'name',
    length: 4,
    type: [sql.VarChar],
    scale: undefined,
    precision: undefined,
    nullable: false,
    caseSensitive: false,
    identity: false,
    readOnly: true
  },
  {
    index: 1,
    name: 'other_name',
    length: 6,
    type: [sql.VarChar],
    scale: undefined,
    precision: undefined,
    nullable: false,
    caseSensitive: false,
    identity: false,
    readOnly: true
  },
  {
    index: 2,
    name: 'name',
    length: 3,
    type: [sql.VarChar],
    scale: undefined,
    precision: undefined,
    nullable: false,
    caseSensitive: false,
    identity: false,
    readOnly: true
  }
]

Errors

There are 4 types of errors you can handle:

  • ConnectionError - Errors related to connections and connection pool.
  • TransactionError - Errors related to creating, committing and rolling back transactions.
  • RequestError - Errors related to queries and stored procedures execution.
  • PreparedStatementError - Errors related to prepared statements.

Those errors are initialized in node-mssql module and its original stack may be cropped. You can always access original error with err.originalError.

SQL Server may generate more than one error for one request so you can access preceding errors with err.precedingErrors.

Error Codes

Each known error has name, code and message properties.

Name | Code | Message :--- | :--- | :--- ConnectionError | ELOGIN | Login failed. ConnectionError | ETIMEOUT | Connection timeout. ConnectionError | EDRIVER | Unknown driver. ConnectionError | EALREADYCONNECTED | Database is already connected! ConnectionError | EALREADYCONNECTING | Already connecting to database! ConnectionError | ENOTOPEN | Connection not yet open. ConnectionError | EINSTLOOKUP | Instance lookup failed. ConnectionError | ESOCKET | Socket error. ConnectionError | ECONNCLOSED | Connection is closed. TransactionError | ENOTBEGUN | Transaction has not begun. TransactionError | EALREADYBEGUN | Transaction has already begun. TransactionError | EREQINPROG | Can't commit/rollback transaction. There is a request in progress. TransactionError | EABORT | Transaction has been aborted. RequestError | EREQUEST | Message from SQL Server. Error object contains additional details. RequestError | ECANCEL | Cancelled. RequestError | ETIMEOUT | Request timeout. RequestError | EARGS | Invalid number of arguments. RequestError | EINJECT | SQL injection warning. RequestError | ENOCONN | No connection is specified for that request. PreparedStatementError | EARGS | Invalid number of arguments. PreparedStatementError | EINJECT | SQL injection warning. PreparedStatementError | EALREADYPREPARED | Statement is already prepared. PreparedStatementError | ENOTPREPARED | Statement is not prepared.

Detailed SQL Errors

SQL errors (RequestError with err.code equal to EREQUEST) contains additional details.

  • err.number - The error number.
  • err.state - The error state, used as a modifier to the number.
  • err.class - The class (severity) of the error. A class of less than 10 indicates an informational message. Detailed explanation can be found here.
  • err.lineNumber - The line number in the SQL batch or stored procedure that caused the error. Line numbers begin at 1; therefore, if the line number is not applicable to the message, the value of LineNumber will be 0.
  • err.serverName - The server name.
  • err.procName - The stored procedure name.

Informational messages

To receive informational messages generated by PRINT or RAISERROR commands use:

const request = new sql.Request()
request.on('info', info => {
    console.dir(info)
})
request.query('print \'Hello world.\';', (err, result) => {
    // ...
})

Structure of informational message:

  • info.message - Message.
  • info.number - The message number.
  • info.state - The message state, used as a modifier to the number.
  • info.class - The class (severity) of the message. Equal or lower than 10. Detailed explanation can be found here.
  • info.lineNumber - The line number in the SQL batch or stored procedure that generated the message. Line numbers begin at 1; therefore, if the line number is not applicable to the message, the value of LineNumber will be 0.
  • info.serverName - The server name.
  • info.procName - The stored procedure name.

Metadata

Recordset metadata are accessible through the recordset.columns property.

const request = new sql.Request()
request.query('select convert(decimal(18, 4), 1) as first, \'asdf\' as second', (err, result) => {
    console.dir(result.recordset.columns)

    console.log(result.recordset.columns.first.type === sql.Decimal) // true
    console.log(result.recordset.columns.second.type === sql.VarChar) // true
})

Columns structure for example above:

{
    first: {
        index: 0,
        name: 'first',
        length: 17,
        type: [sql.Decimal],
        scale: 4,
        precision: 18,
        nullable: true,
        caseSensitive: false
        identity: false
        readOnly: true
    },
    second: {
        index: 1,
        name: 'second',
        length: 4,
        type: [sql.VarChar],
        nullable: false,
        caseSensitive: false
        identity: false
        readOnly: true
    }
}

Data Types

You can define data types with length/precision/scale:

request.input("name", sql.VarChar, "abc")               // varchar(3)
request.input("name", sql.VarChar(50), "abc")           // varchar(50)
request.input("name", sql.VarChar(sql.MAX), "abc")      // varchar(MAX)
request.output("name", sql.VarChar)                     // varchar(8000)
request.output("name", sql.VarChar, "abc")              // varchar(3)

request.input("name", sql.Decimal, 155.33)              // decimal(18, 0)
request.input("name", sql.Decimal(10), 155.33)          // decimal(10, 0)
request.input("name", sql.Decimal(10, 2), 155.33)       // decimal(10, 2)

request.input("name", sql.DateTime2, new Date())        // datetime2(7)
request.input("name", sql.DateTime2(5), new Date())     // datetime2(5)

List of supported data types:

sql.Bit
sql.BigInt
sql.Decimal ([precision], [scale])
sql.Float
sql.Int
sql.Money
sql.Numeric ([precision], [scale])
sql.SmallInt
sql.SmallMoney
sql.Real
sql.TinyInt

sql.Char ([length])
sql.NChar ([length])
sql.Text
sql.NText
sql.VarChar ([length])
sql.NVarChar ([length])
sql.Xml

sql.Time ([scale])
sql.Date
sql.DateTime
sql.DateTime2 ([scale])
sql.DateTimeOffset ([scale])
sql.SmallDateTime

sql.UniqueIdentifier

sql.Variant

sql.Binary
sql.VarBinary ([length])
sql.Image

sql.UDT
sql.Geography
sql.Geometry

To setup MAX length for VarChar, NVarChar and VarBinary use sql.MAX length. Types sql.XML and sql.Variant are not supported as input parameters.

SQL injection

This module has built-in SQL injection protection. Always use parameters or tagged template literals to pass sanitized values to your queries.

const request = new sql.Request()
request.input('myval', sql.VarChar, '-- commented')
request.query('select @myval as myval', (err, result) => {
    console.dir(result)
})

Known issues

Tedious

  • If you're facing problems with connecting SQL Server 2000, try setting the default TDS version to 7.1 with config.options.tdsVersion = '7_1' (issue)
  • If you're executing a statement longer than 4000 chars on SQL Server 2000, always use batch instead of query (issue)

6.x to 7.x changes (pre-release)

  • Upgraded tedious version to v8
  • Requests in stream mode that pipe into other streams no longer pass errors up the stream chain
  • tedious config option trustServerCertificate defaults to false if not supplied

5.x to 6.x changes

  • Upgraded tarn.js so _poolDestroy can take advantage of being a promise
  • ConnectionPool.close() now returns a promise / callbacks will be executed once closing of the pool is complete; you must make sure that connections are properly released back to the pool otherwise the pool