# Changing & Deleting Data

- [DELETE](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/changing-deleting-data/delete.md): Complete guide to deleting data in MariaDB. Complete DELETE syntax with WHERE filtering, JOIN operations, CTEs, and safety considerations for production use.
- [HIGH\_PRIORITY and LOW\_PRIORITY](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/changing-deleting-data/high_priority-and-low_priority.md): Control locking priority for table access. These modifiers determine whether read or write operations take precedence when multiple threads access a table.
- [REPLACE](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/changing-deleting-data/replace.md): Insert or replace rows based on unique keys. This statement acts like INSERT, but if a duplicate key exists, it deletes the old row and inserts the new one.
- [REPLACE...RETURNING](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/changing-deleting-data/replacereturning.md): Replace rows and retrieve the results immediately. This extension returns the values of the replaced or inserted rows in the same operation.
- [UPDATE](https://mariadb.com/docs/server/reference/sql-statements/data-manipulation/changing-deleting-data/update.md): Complete UPDATE statement guide for MariaDB. Complete syntax reference with WHERE conditions, JOIN operations, CTEs, and multi-table updates for production use.


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