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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

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;