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BEGIN...END (Transact-SQL)

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric SQL database in Microsoft Fabric

Encloses a series of Transact-SQL statements so that a group of Transact-SQL statements can be executed in a logical block of code. BEGIN and END are control-of-flow language keywords.

Transact-SQL syntax conventions

Syntax

BEGIN
    { sql_statement | statement_block }
END

Arguments

{ sql_statement | statement_block }

Any valid Transact-SQL statement or statement grouping as defined by using a statement block.

Remarks

BEGIN...END blocks can be nested.

Although all Transact-SQL statements are valid within a BEGIN...END block, certain Transact-SQL statements shouldn't be grouped together within the same batch, or statement block.

Examples

In the following example, BEGIN and END define a series of Transact-SQL statements that execute together. If the BEGIN...END block isn't included, both ROLLBACK TRANSACTION statements would execute, and both PRINT messages would be returned.

USE AdventureWorks2022;
GO

BEGIN TRANSACTION
GO

IF @@TRANCOUNT = 0
BEGIN
    SELECT FirstName, MiddleName
    FROM Person.Person
    WHERE LastName = 'Adams';

    ROLLBACK TRANSACTION;

    PRINT N'Rolling back the transaction two times would cause an error.';
END;

ROLLBACK TRANSACTION;

PRINT N'Rolled back the transaction.';
GO

Examples: Azure Synapse Analytics and Analytics Platform System (PDW)

In the following example, BEGIN and END define a series of SQL statements that run together. If the BEGIN...END block isn't included, the following example runs in a continuous loop.

-- Uses AdventureWorksDW

DECLARE @Iteration INT = 0;

WHILE @Iteration < 10
BEGIN
    SELECT FirstName,
        MiddleName
    FROM dbo.DimCustomer
    WHERE LastName = 'Adams';

    SET @Iteration += 1;
END;