如何在php中保持mysql连接存活

Question

I have a script which loops over tables and fields doing a find and replace. The script takes around 4 minutes to complete. The database is about 1.5GB.

The problem is that I am somehow loosing the database connection. I am using ADODB to connect to mySQL. The db connection is opened at the beginning and remains open the whole duration of the script.

The problem disappears when I use the following code:

if ($rowCount % 100000 == 0) {
    $db->Execute('USE ' . $db->database);
}

I am not a fan of this solution!

Any suggestions/explanations/discussions that help me to stop scratching my head would be greatly appreciated!

Answer 1

Use mysqli::ping() to determine if connection is alive. Connect again if not.

Checks whether the connection to the server is working. If it has gone down, and global option mysqli.reconnect is enabled an automatic reconnection is attempted.

This function can be used by clients that remain idle for a long while, to check whether the server has closed the connection and reconnect if necessary.

Answer 2

The word you're looking for is 'persistent', and the answer you're looking for is here:

mysqli persistent connection

Answer 3

You can use one of these methods to make a persistent connection to mysql:

Mysqli

Try using mysqli_connect() with p: prefix for host name.

PDO

Try using PDO::__construct() with PDO::ATTR_PERSISTENT as a driver option.

Answer 4

You could use mysql_pconnect(); or equally for ADODB $conn->PConnect(); to create a persistent connection