[ statement-label : ]
BEGIN TRY
   [ local-declaration; ... ]
   [ statement-list ]
END TRY
BEGIN CATCH
   [ statement-list ]
END CATCH

local-declaration :
variable-declaration
| cursor-declaration
| exception-declaration
| temporary-table-declaration

variable-declaration and exception-declaration : See DECLARE statement.

cursor-declaration : See DECLARE CURSOR statement [ESQL] [SP].

temporary-table-declaration : See DECLARE LOCAL TEMPORARY TABLE statement.

The CATCH block is the error handler for the TRY statement.

TRY...CATCH statements can be nested and used anywhere that a BEGIN...END statement can be used. Statements within the TRY block ignore the on_tsql_error and continue_after_raiserror database options, as well as the ON EXCEPTION RESUME clause of the CREATE PROCEDURE statement. TRY...CATCH statements are not atomic.

If no errors occur in the TRY block, the CATCH block is skipped and control passes to the statement following the CATCH block or the caller if no such statement exists. If an error occurs in one of the statements in the TRY block, control passes to the first statement in the CATCH block. Once the CATCH block completes, control passes to the statement following the CATCH block or the caller if no such statement exists. The effect of statements that precede a statement that generates an error is not reverted unless the exception handler generates an error and is nested within an atomic block or an explicit ROLLBACK statement is called. In this case, all statements within the atomic transaction block are reverted.

Errors in the CATCH block are handled according to the connection and procedure settings unless the statements generating them are enclosed in additional TRY...CATCH statements.

None.

None.

• ERROR_LINE function [Miscellaneous]
• ERROR_MESSAGE function [Miscellaneous]
• ERROR_PROCEDURE function [function type]
• ERROR_SQLCODE function [Miscellaneous]
• ERROR_SQLSTATE function [Miscellaneous]
• ERROR_STACK_TRACE function [Miscellaneous]
• STACK_TRACE function [Miscellaneous]
• sa_error_stack_trace system procedure
• sa_stack_trace system procedure
• Nested compound statements and exception handlers
• Stored procedures, triggers, batches, and user-defined functions
• Error and warning handling
• Exception handling and atomic compound statements
• Exception handlers
• Atomic compound statements
• CONTINUE statement
• SIGNAL statement [SP]
• RESIGNAL statement [SP]
• RAISERROR statement
• BEGIN statement [TSQL]

These examples use the following table:

CREATE TABLE t( col1 DOUBLE );

Executing the following compound statement inserts value 6 into table t:

BEGIN TRY
    DECLARE val INT;

    SET val = 0;

    INSERT INTO t VALUES( 1 / val );
    -- This statement will not be executed
    INSERT INTO t VALUES( val );
END TRY
BEGIN CATCH
    SET val = 6;
    INSERT INTO t VALUES( val );
END CATCH;

Executing the following procedure by using CALL proc1(10); inserts the following values into the table t:

CREATE PROCEDURE DBA.proc1( v INTEGER )
BEGIN TRY
    DECLARE local_val INTEGER = 0;

    INSERT INTO t VALUES(-v);

    SET local_val = v / local_val;
    -- This statement will not be executed
    MESSAGE 'The value is ', v;
END TRY
BEGIN CATCH
    INSERT INTO t VALUES(v);
END CATCH;