IS_NOT_NULL()

All functions > COMPARISON > IS_NOT_NULL()

Returns TRUE if the expression does NOT evaluate to NULL.

Signatures

Returns: TRUE or FALSE; these predicates do not return NULL themselves

IS_NOT_NULL(expr: T) → BOOLEAN

Notes

• Opposite of IS NULL
• Only reliable way to test for non-NULL values
• Using != NULL always returns NULL, not TRUE/FALSE
• Works with any data type (scalars, ARRAY, ROW, etc.); optional ::type after the keyword must match the expression type when present
• Never returns NULL itself - always Returns TRUE or FALSE

Related operators

• IS NOT NULL

Examples

IS_NOT_NULL — functional call (second arg is TYPE '…')

SELECT
    f1 := IS_NOT_NULL('x', TYPE 'VARCHAR'), -- Non-NULL string
    f2 := IS_NOT_NULL(NULL::BIGINT, TYPE 'BIGINT') -- NULL is not non-NULL
;

IS_NOT_NULL — chained

SELECT
    f1 := ('x').IS_NOT_NULL(TYPE 'VARCHAR'), -- Dot form: receiver is the expression under test
    f2 := (NULL::BIGINT).IS_NOT_NULL(TYPE 'BIGINT') -- Same semantics as the prefix call
;