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sqlsrv_begin_transaction

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Begins a transaction on a specified connection. The current transaction includes all statements on the specified connection that were executed after the call to sqlsrv_begin_transaction and before any calls to sqlsrv_rollback or sqlsrv_commit.

Note

The Microsoft Drivers for PHP for SQL Server is in auto-commit mode by default. This means that all queries are automatically committed upon success unless they have been designated as part of an explicit transaction by using sqlsrv_begin_transaction.

Note

If sqlsrv_begin_transaction is called after a transaction has already been initiated on the connection but not completed by calling either sqlsrv_commit or sqlsrv_rollback, the call returns false and an Already in Transaction error is added to the error collection.

Syntax

  
sqlsrv_begin_transaction( resource $conn)  

Parameters

$conn: The connection with which the transaction is associated.

Return Value

A Boolean value: true if the transaction was successfully begun. Otherwise, false.

Example

The example below executes two queries as part of a transaction. If both queries are successful, the transaction is committed. If either (or both) of the queries fail, the transaction is rolled back.

The first query in the example inserts a new sales order into the Sales.SalesOrderDetail table of the AdventureWorks database. The order is for five units of the product that has product ID 709. The second query reduces the inventory quantity of product ID 709 by five units. These queries are included in a transaction because both queries must be successful for the database to accurately reflect the state of orders and product availability.

The example assumes that SQL Server and the AdventureWorks database are installed on the local computer. All output is written to the console when the example is run from the command line.

<?php  
/* Connect to the local server using Windows Authentication and  
specify the AdventureWorks database as the database in use. */  
$serverName = "(local)";  
$connectionInfo = array( "Database"=>"AdventureWorks");  
$conn = sqlsrv_connect( $serverName, $connectionInfo);  
if( $conn === false )  
{  
     echo "Could not connect.\n";  
     die( print_r( sqlsrv_errors(), true ));  
}  
  
/* Initiate transaction. */  
/* Exit script if transaction cannot be initiated. */  
if ( sqlsrv_begin_transaction( $conn ) === false )  
{  
     echo "Could not begin transaction.\n";  
     die( print_r( sqlsrv_errors(), true ));  
}  
  
/* Initialize parameter values. */  
$orderId = 43659; $qty = 5; $productId = 709;  
$offerId = 1; $price = 5.70;  
  
/* Set up and execute the first query. */  
$tsql1 = "INSERT INTO Sales.SalesOrderDetail   
                     (SalesOrderID,   
                      OrderQty,   
                      ProductID,   
                      SpecialOfferID,   
                      UnitPrice)  
          VALUES (?, ?, ?, ?, ?)";  
$params1 = array( $orderId, $qty, $productId, $offerId, $price);  
$stmt1 = sqlsrv_query( $conn, $tsql1, $params1 );  
  
/* Set up and execute the second query. */  
$tsql2 = "UPDATE Production.ProductInventory   
          SET Quantity = (Quantity - ?)   
          WHERE ProductID = ?";  
$params2 = array($qty, $productId);  
$stmt2 = sqlsrv_query( $conn, $tsql2, $params2 );  
  
/* If both queries were successful, commit the transaction. */  
/* Otherwise, rollback the transaction. */  
if( $stmt1 && $stmt2 )  
{  
     sqlsrv_commit( $conn );  
     echo "Transaction was committed.\n";  
}  
else  
{  
     sqlsrv_rollback( $conn );  
     echo "Transaction was rolled back.\n";  
}  
  
/* Free statement and connection resources. */  
sqlsrv_free_stmt( $stmt1);  
sqlsrv_free_stmt( $stmt2);  
sqlsrv_close( $conn);  
?>  

For the purpose of focusing on transaction behavior, some recommended error handling is not included in the example above. For a production application, it is recommended that any call to a sqlsrv function be checked for errors and handled accordingly.

Note

Do not use embedded Transact-SQL to perform transactions. For example, do not execute a statement with "BEGIN TRANSACTION" as the Transact-SQL query to begin a transaction. The expected transactional behavior cannot be guaranteed when using embedded Transact-SQL to perform transactions.

See Also

SQLSRV Driver API Reference

How to: Perform Transactions

Overview of the Microsoft Drivers for PHP for SQL Server