Mørch for this advice in the comments.Įxample technique was from Baron Schwartz, originally published at Nabble, paraphrased and extended here. SET optimizer_switch = 'derived_merge=off' Luckily, the optimizer_switch variable can be used to switch off this behaviour although I couldn't recommend doing this as anything more than a short term fix, or for small one-off tasks. However, beware that from MySQL 5.7.6 and onward, the optimiser may optimise out the subquery, and still give you the error. Table, so it doesn't count as the same table you're updating. The nested subquery in the FROM clause creates an implicit temporary The following examples demonstrate how to use ALTER TABLE to add and then drop a basic table column and also how to drop a column with a dependent object. Ugly for several reasons, including performance: UPDATE tbl SET col = ( If you absolutely need the subquery, there's a workaround, but it's UPDATE tbl AS aĪlternatively, try nesting the subquery deeper into a from clause. This will cause MySQL to see the table as two different things, allowing destructive changes to go ahead. Here is a tutorial script to delete an existing column: mysql> ALTER TABLE tip DROP COLUMN createdate Query OK, 1 row affected (0.48 sec) Records: 1. If the logic is simple enough to re-shape the query, lose the subquery and join the table to itself, employing appropriate selection criteria. Maybe you can just join the table to itself In MySQL, you can't modify the same table which you use in the SELECT part. For a more specific answer about how to best handle the OP's exact query, please see other answers to this question 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.Update: This answer covers the general error classification.
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