GREATEST(...)

All functions > COMPARISON > GREATEST(...)

Returns the greatest (maximum) value from a list of arguments.

Signatures

Returns: Greatest of the arguments, or NULL if any argument is NULL

GREATEST_FN(exprs: T, ...) → T

Notes

• All arguments must be of the same or compatible types
• If any argument is NULL, the result is NULL
• For strings, uses lexicographic (dictionary) ordering
• For dates/timestamps, returns the latest date/time
• For ARRAY and ROW, uses the same ordering as < / > (see Related operators for variadic GREATEST(...) examples)
• Can accept any number of arguments (not just two)
• Equivalent to finding the maximum value across multiple columns
• Opposite of LEAST function

Related operators

• GREATEST(...)

Examples

GREATEST_FN — single-array encoding

SELECT
    -- Same semantics as variadic `GREATEST`
    f1 := GREATEST_FN(ARRAY(1, 5, 3)),
    -- Lexicographic max via array encoding
    f2 := GREATEST_FN(ARRAY('a', 'z', 'm'))
;

GREATEST_FN — NULL propagation

SELECT
    -- Any NULL in the list → NULL result
    f1 := GREATEST_FN(ARRAY(NULL::BIGINT, 3)),
    -- NULL anywhere → NULL result
    f2 := GREATEST_FN(ARRAY(1, NULL::BIGINT, 3))
;

GREATEST_FN — arrays of arrays

SELECT
    -- Lexicographic max of two array values
    f1 := GREATEST_FN(ARRAY(ARRAY(1, 1), ARRAY(1, 2)))
;