Replaces the substring of string that starts at the start'th character and extends for count characters with newsubstring.
overlay ( string text PLACING newsubstring text FROM start integer [ FOR count integer ] ) → textReplaces the substring of
string that starts at the start'th character and extends for count characters with newsubstring. If count is omitted, it defaults to the length of newsubstring.overlay('Txxxxas' placing 'hom' from 2 for 4) → Thomasoverlay ( bytes bytea PLACING newsubstring bytea FROM start integer [ FOR count integer ] ) → byteaReplaces the substring of
bytes that starts at the start'th byte and extends for count bytes with newsubstring. If count is omitted, it defaults to the length of newsubstring.overlay('\x1234567890'::bytea placing '\002\003'::bytea from 2 for 3) → \x12020390overlay ( bits bit PLACING newsubstring bit FROM start integer [ FOR count integer ] ) → bitReplaces the substring of
bits that starts at the start'th bit and extends for count bits with newsubstring. If count is omitted, it defaults to the length of newsubstring.overlay(B'01010101010101010' placing B'11111' from 2 for 3) → 0111110101010101010
Definition snapshot: 2026-09-14T13:14:25.684213+00:00@99e6866c · English manual source