REGEXP_COUNT

Counts how many times a regular expression matches in a string.

PostgreSQL 17.9

REGEXP_COUNT(string, pattern[, start[, flags]])

Return value

An integer; 0 if there are no matches

PostgreSQL 17.9

SELECT REGEXP_COUNT('a1b22c333', '[0-9]+') AS numbers,
	REGEXP_COUNT('a1b22c333', '[0-9]') AS digits;

numbers	digits
3	6

PostgreSQL 17.9

SELECT member_name,
	REGEXP_COUNT(member_name, '[aeiou]', 1, 'i') AS vowels
FROM FamilyMembers;

The function appeared in PostgreSQL 15. Matches do not overlap: in the string 'aaa' the pattern 'aa' is found once.