from MySQL: how to drop multiple tables using single query?




teradata drop multiple tables (6)

Go to c:\xampp\mysql\data\your folder

Select multiple tables that you want remove and then press delete button

Thanks

I want to drop multiple tables with ease without actually listing the table names in the drop query and the tables to be deleted have prefix say 'wp_'


For the great mysqldump solution it's better to use the option --skip-quote-names

mysqldump --skip-quote-names -u user -p database > dump.sql 
grep "DROP TABLE wp_" dump.sql > drop.sql
mysql -u user -p database < drop.sql

You get rid of backticks in table names. The grep part won't work in some enviroments with the backticks.


Simple solution without risk of error:

mysqldump create a file that contains DROP command like

DROP TABLE IF EXISTS `wp_matable`;

a 'grep' with "DROP TABLE wp_" give us the commands to execute

so drop is made by theses trhee lines (you can edit drop.sql to check which tables would be dropped before)

mysqldump -u user -p database > dump.sql 
grep "DROP TABLE `wp_" dump.sql > drop.sql
mysql -u user -p database < drop.sql

I've used a query very similar to Angelin's. In case you have more than a few tables, one has to increase the max length of group_concat. Otherwise the query will barf on the truncated string that group_concat returns.

This is my 10 cents:

-- Increase memory to avoid truncating string, adjust according to your needs
SET group_concat_max_len = 1024 * 1024 * 10;
-- Generate drop command and assign to variable
SELECT CONCAT('DROP TABLE ',GROUP_CONCAT(CONCAT(table_schema,'.',table_name)),';') INTO @dropcmd FROM information_schema.tables WHERE table_schema='databasename' AND table_name LIKE 'my_table%';
-- Drop tables
PREPARE str FROM @dropcmd; EXECUTE str; DEALLOCATE PREPARE str;

Dropping single table in mysql:

DROP TABLE TABLE_NAME;


Be careful with "_", need to be written with "\" before in Mysql like:

SELECT CONCAT('DROP TABLE',GROUP_CONCAT(CONCAT(table_schema,'.',table_name)),';') INTO @dropcmd FROM information_schema.tables WHERE table_schema='databasename' AND table_name LIKE '**my\\_table**%';






multiple-tables