CASE_WHEN

All functions > CONDITIONAL > CASE_WHEN

Returns the result of the first condition that evaluates to true

Signatures

Returns: the value corresponding to the first true condition, or else value if none match

CASE_WHEN(when: ARRAY<BOOLEAN>, then: ARRAY<T>, [else: T]) → T

Notes

• Evaluates conditions in order and returns the first matching result
• when and then arrays must have the same length
• If no condition matches and else is not provided, returns NULL
• Short-circuits: stops evaluating once a condition is true
• All then values and else value must be of compatible types

Examples

SELECT
    f1 := CASE_WHEN(ARRAY[FALSE, TRUE, FALSE], ARRAY[1, 2, 3], 999),  -- Second condition matches
    f2 := CASE_WHEN(ARRAY[FALSE, FALSE], ARRAY[1, 2], 999),  -- No condition matches, returns else value
    f3 := CASE_WHEN(ARRAY[TRUE, TRUE], ARRAY[1, 2], 999),  -- First condition matches (short-circuits)
    f4 := CASE_WHEN(ARRAY[FALSE, FALSE], ARRAY[1, 2])  -- No match, no else, returns NULL
;