(PHP 5, PHP 7) Open a connection to a database

(PECL CUBRID >= 8.4.0) Get result of next query when executing multiple SQL statements

(PHP 5, PHP 7, PECL OCI8 >= 1.1.0) Returns the next row from a query as an associative array

(PHP 5, PHP 7, PECL OCI8 >= 1.1.0) Tests for end-of-file on a large object's descriptor

(PHP 5, PHP 7) Get MySQL client info string

(PHP 4 >= 4.0.2, PHP 5 <= 5.0.5, PECL ingres >= 1.0.0) Test if a field is nullable

(PECL mongo >=0.9.0) Fetches the document pointed to by a database reference

(PECL ibm_db2 >= 1.0.0) Returns a result set listing the index and statistics for a table

(PHP 4, PHP 5, PHP 7) Get result data string

(PHP 5 >= 5.3.0, PHP 7) Returns the SQLite3 library version as a string constant and as a number