int pg_exec (int connection, string query)
Returns a result index if query could be executed, false on failure or if connection is not a valid connection index. Details about the error can be retrieved using the pg_ErrorMessage() function if connection is valid. Sends an SQL statement to the PostgreSQL database specified by the connection index. The connection must be a valid index that was returned by pg_Connect(). The return value of this function is an index to be used to access the results from other PostgreSQL functions.
Note: PHP/FI returned 1 if the query was not expected to return data (inserts or updates, for example) and greater than 1 even on selects that did not return anything. No such assumption can be made in PHP.