php5 NÃO tem biblioteca nativa de MySql

DatabasesThere were some changes in PHP 5 regarding databases (MySQL and SQLite). In PHP 5 the MySQL client libraries are not bundled, because of license problems and some others. For more information, read the FAQ entry. There is also a new extension, MySQLi (Improved MySQL), which is designed to work with MySQL 4.1 and above. Since PHP 5, the SQLite extension is built-in PHP. SQLite is an embeddable SQL database engine and is not a client library used to connect to a big database server (like MySQL or PostgreSQL). The SQLite library reads and writes directly to and from the database files on disk.

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