


How Can I Connect to Multiple MySQL Databases from a Single PHP Webpage?
Dec 13, 2024 am 01:19 AMConnecting 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.
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