GREATEST

All functions > COMPARISON > GREATEST

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

Syntax

Diagram(
  Sequence(
    Terminal("GREATEST"),
    Terminal("("),
    NonTerminal("expr"),
    Terminal(","),
    OneOrMore(NonTerminal("expr"), Terminal(",")),
    Terminal(")"),
  )
)

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
• Can accept any number of arguments (not just two)
• Equivalent to finding the maximum value across multiple columns
• Opposite of LEAST function

Examples

Numeric values

SELECT
    f1 := GREATEST(1, 5, 3),  -- Numeric maximum
    f2 := GREATEST(1, 1, 1),  -- All same values
    f3 := GREATEST(-5, -1, -10),  -- Negative numbers
    f4 := GREATEST(NULL::BIGINT, 5, 3)  -- NULL input
;

Other types

SELECT
    f1 := GREATEST('apple', 'banana', 'cherry'),  -- String maximum
    f2 := GREATEST('a', 'A'),  -- Case sensitive
    f3 := GREATEST(1.5, 2.3, 1.1)  -- Decimal numbers
;