![]() The above example is based on: MySQL – Delete/Drop all tables with specific prefix. For example, you can add or delete columns, create or destroy indexes, change the type. 40,000 rows takes 15 minutes, 100,000 rows runs for well over an hour. ALTER TABLE enables you to change the structure of an existing table. If deleting 15,000 rows it runs in about 15 seconds. ![]() PREPARE drop_statement FROM 'DELETE FROM drop_statement USING PREPARE drop_statement 11 When performing a DELETE against a large number of rows in the Prices table, the DELETE becomes progressively slower. ![]() If you want to use only MySQL for that, you can think of more advanced query, such as this: SET = (SELECT GROUP_CONCAT(TABLE_NAME) FROM information_schema.TABLES WHERE TABLE_NAME LIKE 'table%') More shell oriented example would be: echo "SHOW TABLES LIKE 'table%'" | mysql | tail -n +2 | xargs -L1 -I% echo "DELETE FROM % WHERE user_id=123 " | mysql -v Then pipe it (in shell) into mysql command for execution.įor example it'll generate something like: DELETE FROM table1 WHERE user_id=123 However if all yours tables starts with certain name, then this query will generate query which would do that task: SELECT CONCAT('DELETE FROM ', GROUP_CONCAT(TABLE_NAME SEPARATOR ' WHERE user_id=123 DELETE FROM '), 'FROM table1 ' ) AS statement FROM information_schema.TABLES WHERE TABLE_NAME LIKE 'table%' The syntax for using DROP COLUMN keyword to drop columns in MySQL. ![]() How to Install MySQL Server on CentOS / Redhat 6/7/8 How to Change MySQL User Password How to Enable Slow Query Log in MySQL 5.6 How to Change MySQL Data Directory to New Location on CentOS 7 How to Install MongoDB Server on Ubuntu and Debian Based System How to Install MySQL 8.0 on CentOS, RHEL and Fedora Systems How to Disable Strict SQL Mode in MySQL 5.7 Skip Duplicate Replication Error in MySQL Alter Table Statement in MySQL : How to Add Column in Table How to :- Alter Table or Add Multiple Columns in Table? – MySQL Alter Table Statement in MySQL : How to Modify Column in Table Alter Table Statement in MySQL : How to Rename Table ERROR 1130 (HY000): Host ” is not allowed to connect to this MySQL server How to Setup MySQL Master Slave Replication Using Rsync How to Install and Configure phpMyAdmin on CentOS 7 How to Setup MySQL Master Slave Replication using Percona XtraBackup Fix : Mysql Warning Using a Password on The Command Line Interface Can be Insecure How To Install PostgreSQL 10 On CentOS/RHEL 7/6 and Fedora 26/25 Fix phpMyAdmin :- unblock with ‘mysqladmin flush-hosts’ / Error Host ” is blocked because of many connection How To Install MySQL 8.0 On CentOS, RHEL and Fedora Case study: Alternative Way To Recover MySQL Root Password Installing Percona XtraBackup on RHEL and CentOS Restore Mysqldump Backup Faster How To Setup GTID Replication In MySQL 5.6 MySQL : Show How Many INSERT, UPDATE, DELETE In Binary Log File How To Change MySQL Binary Log File Location To Another Directory Restore MySQL Database From Dump File MySQL Database Backup From The Command Line MySQL Database Backup Automatic Script Steps To Configure Master Slave MySQL Replication How To Extract Tables From MySQL Dump File How To Recover MySQL Root Password How To Connect MySQL Server Without Password Prompt Unable To Connect MySQL Database Server From PHP Steps Before Shutting Down MySQL Server How To Reinstall MySQL Server v5.x On Linux Automated Installation and Configurations – Apache/Nginx, MySQL ,PHP or PHP-FPM on Linux/UNIX How to Find Table & Database Size in MySQL How To Install Only MySQL Client On CentOS/Redhat 6/7/8 or Ubuntu Change MySQL default Data Directory to New Location in Linux Check and Update max_connections value to fix MySQL Error: Too many connections Why You Should Upgrade Your Open Source Database Software? MySQL Basic Commands For Database Administrator Adding Multiple MySQL Database Server In Single PhpMyAdmin Installation Guide :- How to Install MySQL 5.Normally you can't DELETE from multiple tables at once, unless you'll use JOINs as shown in other answers. The MySQL DROP COLUMN keyword is used to a delete columns from an existing table.
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