array_position()

Returns the subscript of the first occurrence of the second argument in the array, or NULL if it's not present. If the third argument is given, the search begins at that subscript. The array must be one-dimensional. Comparisons are done using IS NOT DISTINCT FROM semantics, so it is possible to search for NULL.

Signature

array_position ( anycompatiblearray, anycompatible [, integer ] ) → integer

Examples

SELECT array_position(ARRAY['sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat'], 'mon');

Run against PostgreSQL 18.6 on 2026-09-13. This is the output we got, not the documentation’s.

In other engines

PostgreSQL	array_position
MySQL	FIND_IN_SET(needle, csv)
SQL Server	no direct equivalent
Oracle	no direct equivalent
SQLite	no direct equivalent

Another consequence of PostgreSQL having arrays. FIND_IN_SET is not really the same function — it works on a comma-separated string, which is what you are forced into when the column type does not exist.

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