Locking a Single Row in MyISAM Tables

MyISAM tables only support table-level locking, which means that locking a specific row is not possible. This can be limiting when you need to modify a single row while preventing concurrent access.

Solution for InnoDB Tables

If possible, consider converting your user table to InnoDB. InnoDB provides row-level locking, allowing you to lock a specific row while allowing access to other rows in the same table.

For MyISAM Tables

1. Exclude duplicate queries: Use a unique index on the user field to prevent duplicate queries from locking the same row simultaneously. This can reduce the risk of conflicts and increase concurrency.
2. Use locking mechanisms outside MySQL: If row-level locking is critical, you can implement external locking mechanisms using programming languages or frameworks. For example, you can use a mutex or semaphore to prevent concurrent access to the row within your application.
3. Switch to a different storage engine: MyISAM is not designed for high-concurrency scenarios. Consider switching to a storage engine like Aria or MariaDB ColumnStore that offers row-level locking.

For more information on locking in MySQL, refer to the following documentation:

• [MySQL Documentation: Locks Set by SQL Statements for InnoDB Tables](http://dev.mysql.com/doc/refman/5.0/en/innodb-locks-set.html)