(PHP 4 >= 4.0.6, PHP 5, PHP 7) Get or set the username for the connection

(PHP 5 >= 5.3.3, Bundled pdo_pgsql, PHP 7) Checks if inside a transaction

(PHP 5, PHP 7) Pings a server connection, or tries to reconnect if the connection has gone down

(PECL ibm_db2 >= 1.0.0) Returns the width of the current value of the indicated column in a result set

(PECL CUBRID >= 8.4.1) Set the timeout time of query execution

(PECL CUBRID >= 8.3.0) Read data from a GLO instance and save it in a file

(PHP 5, PHP 7, PECL OCI8 >= 1.1.0) Appends data from the large object to another large object

(PECL tokyo_tyrant >= 0.1.0) The get purpose

(PHP 5 < 5.4.0, PECL sqlite >= 1.0.0) Seek to the next row number

(PHP 4, PHP 5, PHP 7) Retrieves information about data types supported by the data source