Locking All Tables Across Databases in mysqldump

The mysqldump command in MySQL is used to create backups of MySQL databases. One of its options, -x or --lock-all-tables, ensures that all tables across databases are locked during the dump operation. This is particularly useful to maintain data consistency when performing backups, preventing changes to the database schema or data during the backup process.

Here are several examples demonstrating the usage of -x, --lock-all-tables in mysqldump:

Example 1: Dumping a single database with all tables locked:
mysqldump -x -u username -p dbname > backup.sql

Explanation: This command dumps the database dbname while locking all its tables, ensuring data consistency throughout the backup process.

Example 2: Dumping all databases on the server with table locking:
mysqldump -x -u username -p --all-databases > all_databases_backup.sql

Explanation: This command dumps all databases on the MySQL server into a single backup file all_databases_backup.sql, locking tables across all databases to maintain consistency.

Example 3: Dumping a database and excluding certain tables, with table locking:
mysqldump -x -u username -p dbname --ignore-table=dbname.table1 --ignore-table=dbname.table2 > backup_excluding_tables.sql

Explanation: This command dumps the database dbname while excluding specific tables table1 and table2, and ensures that all other tables are locked during the dump.

Example 4: Dumping a database and compressing the output file, with table locking:
mysqldump -x -u username -p dbname | gzip > backup.sql.gz

Explanation: This command dumps the database dbname while locking all its tables, then compresses the output file backup.sql using gzip.

Example 5: Dumping a specific table with table locking:
mysqldump -x -u username -p dbname table_name > table_backup.sql

Explanation: This command dumps the specified table table_name from the database dbname, locking the table during the operation to ensure data consistency.

Verification: To verify whether the table locking worked as intended, you can inspect the backup file or check the MySQL logs for any entries related to table locks during the dump process. Additionally, you can attempt to perform updates or inserts on the database while the dump is in progress to see if they are blocked due to table locking.

Also check similar articles.

Setting Line Terminator in mysqldump Output
Using INSERT IGNORE Statements in mysqldump
Including Master Host and Port in mysqldump Output (Deprecated)
Including Source Host and Port in mysqldump Output
Ignoring Tables During mysqldump