DISPLAYS_AS()

All functions > COMPARISON > DISPLAYS_AS()

Returns TRUE if two values are not distinct, treating NULL values as comparable.

Signatures

Returns: Null-safe equality / inequality result

DISPLAYS_AS(expr1: T, expr2: T) → BOOLEAN

Notes

• Unlike =, NULL is treated as comparable here (null-safe equality)
• NULL DISPLAYS AS NULL is TRUE (they are the same)
• value DISPLAYS AS NULL is FALSE when value is not NULL
• Nested NULL inside ARRAY/ROW is compared null-safely at every nesting level
• Both values must be of the same type (including ARRAY/ROW)
• Opposite of NOT DISPLAYS AS
• FeatureQL-native spelling; SQL IS NOT DISTINCT FROM is registered separately so format/querytools match the syntax you used

Related operators

• DISPLAYS AS

See also

• IS_NOT_DISTINCT_FROM

Examples

DISPLAYS_AS — functional call

SELECT
    -- `DISPLAYS_AS(expr1, expr2)` matches keyword `DISPLAYS AS`
    f1 := DISPLAYS_AS(1, 1),
    -- Both NULL: null-safe equality
    f2 := DISPLAYS_AS(NULL::BIGINT, NULL::BIGINT),
    -- Nested NULL fields match
    f3 := DISPLAYS_AS(
        ROW(1::BIGINT, NULL::BIGINT),
        ROW(1::BIGINT, NULL::BIGINT)
    )
;

DISPLAYS_AS — chained

SELECT
    -- Receiver is the left-hand operand
    f1 := (1).DISPLAYS_AS(1),
    -- Same semantics as the prefix call
    f2 := (NULL::BIGINT).DISPLAYS_AS(NULL::BIGINT)
;