2013/3/13 Thor Michael Støre <thormichael@xxxxxxxxx>: > Hello, > > Could someone make sense of this for me? > > $ /Library/PostgreSQL/9.2/bin/psql -d postgres postgres > psql (9.2.3) > Type "help" for help. > > postgres=# select 1 = ANY (ARRAY[1,2,3]); > ?column? > ---------- > t > (1 row) > > postgres=# select 1 = ANY (SELECT ARRAY[1,2,3]); > ERROR: operator does not exist: integer = integer[] > LINE 1: select 1 = ANY (SELECT ARRAY[1,2,3]); > ^ > HINT: No operator matches the given name and argument type(s). You might > need to add explicit type casts. > postgres=# select 1 = ANY ((SELECT ARRAY[1,2,3])::int[]); > ?column? > ---------- > t > (1 row) > > Why do I have to add an explicit cast to int array on something that is an > int array to begin with? Based on the error message containing "integer = > integer[]" I'd say PostgreSQL manages to figure out the right type anyhow, > and ::int[] shouldn't change anything, but I still get a message that > doesn't make sense when I have an ANY there. A bit tricky to explain... select 1 = ANY (ARRAY[1,2,3]) -> "Is the integer value 1 contained in the specified array of integers?" (YES) select 1 = ANY (SELECT ARRAY[1,2,3]) -> "Is the integer value 1 contained in the specified result set, which happens to be an array (which is not comparable with an integer)?" (NO) select 1 = ANY ((SELECT ARRAY[1,2,3])::int[]); -> "Is the value one contained in an array of integers which is derived by converting a result set into an array?" (YES) Note: testdb=> SELECT array[1,2,3] = ANY (SELECT ARRAY[1,2,3]); ?column? ---------- t (1 row) I hope that makes some kind of sense... Ian Barwick -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
