(PHP 5, PHP 7) Returns an array with client, protocol and server version (when available)

(PHP 4 >= 4.2.0, PHP 5, PHP 7) Sends asynchronous query

(PHP 5 >= 5.1.0, PHP 7) Returns the type ID (OID) for the corresponding field number

(PHP 5 >= 5.4.4, PHP 7) Escape a identifier for insertion into a text field

(PHP 4 >= 4.0.6, PHP 5, PHP 7) Returns the last notice message from PostgreSQL server

(PHP 5 >= 5.1.0, PHP 7) Sends a request to execute a prepared statement with given parameters, and waits

(PHP 4 >= 4.3.0, PHP 5, PHP 7) Ping database connection

(PHP 4 >= 4.3.0, PHP 5, PHP 7) Fetch a row as an associative array

(PHP 4, PHP 5, PHP 7) Open a persistent PostgreSQL connection