Help Center/ GaussDB/ Developer Guide(Centralized_8.x)/ Stored Procedure/ Control Statements/ NULL Statements
Updated on 2024-08-20 GMT+08:00
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NULL Statements

In PL/SQL programs, NULL statements are used to indicate "nothing should be done", equal to placeholders. They grant meanings to some statements and improve program readability.

Syntax

The following shows example use of NULL statements:

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DECLARE
    ...
BEGIN
    ...
    IF v_num IS NULL THEN
        NULL; -- No data needs to be processed.
    END IF;
END;
/

Parameter description:

  • v_num: specifies the variable or expression.

Example

gaussdb=# DECLARE
    v_num integer default NULL;
BEGIN
    IF v_num IS NOT NULL THEN
        raise info 'v_num is NULL'; 
    ELSE
        NULL; -- No data needs to be processed.
    END IF;
END;
/
ANONYMOUS BLOCK EXECUTE
Parent topic: Control Statements