How Can I Connect to Multiple MySQL Databases from a Single PHP Webpage?

Connecting to Multiple MySQL Databases in a Single PHP Webpage

Question:
How to use PHP in a single Connect to multiple MySQL databases on a web page?

Answer:

There are several ways to connect to multiple MySQL databases using PHP.

Use the mysql_connect function:

For the same connection parameters, you can connect to different databases by calling mysql_connect multiple times. However, the fourth parameter $new_link must be set to true to avoid reusing the same connection.

For example:

Select database:

To query a specific database, please pass in the corresponding connection identifier in the query Identifier:

Other options:

In addition to using multiple connections, there are other options:

• Use mysql_select_db: If the MySQL user has access to all databases and they are on the same host, you can use mysql_select_db to switch databases between queries.
• Specify database in query: You can explicitly select a database by specifying the database name in the query, for example: SELECT * FROM database2.tablename.

Note: The

mysql_ function has been removed from PHP 7.0, it is recommended to use the mysqli_ function or PDO.

The above is the detailed content of How Can I Connect to Multiple MySQL Databases from a Single PHP Webpage?. For more information, please follow other related articles on the PHP Chinese website!