There might be inconsistency in overlap operators for array types ( <@, @>, and && ) when the argument arrays contain NULLs.
- SELECT 2 = ANY (ARRAY[1, NULL]) => NULL - SELECT ARRAY[2] <@ ARRAY[1, NULL] => false NULL means "unknown" in definition, so should it return NULL rather than false? I found the issue when I read spec of MULTISET. In the SQL standard, the following expression returns NULL. I was thinking to make SUBMULTISET OF to be an alias of <@ operator, but they seems to be incompatible. - MULTISET[2] SUBMULTISET OF MULTISET[1, NULL] => NULL Will we change the operator's behavior? It would be more consistent, but incompatible with older server versions. If impossible, I'll add separated submultiset_of() function instead of <@ operator for MULTISET supports. -- Itagaki Takahiro -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
