How can I delete all the triggers in a MySQL database using one SQL statement?

Unfortunately this is not possible in a regular SQL statement or a stored procedure.

Solution

The simplest solution to drop all triggers might be a bash script:

echo "select concat('drop trigger ', trigger_name, ';')
  from information_schema.triggers where trigger_schema = 'your_database'" |
  mysql --defaults-extra-file=.mysql.conf --disable-column-names | 
  mysql --defaults-extra-file=.mysql.conf

This requires a credentials file (.mysql.conf) like so:

[client]
database=your_database
user=your_username
password=your_password

Reasoning

Attempting to drop a trigger from a stored procedure will fail. I'm guessing this happens because a variable can only hold a string and drop trigger requires a trigger name (not a string containing a trigger name):

create procedure drop_a_trigger()
begin
  declare var1 varchar(1024);
  set var1 = "my_second_trigger";

  drop trigger my_first_trigger;       // OK
  drop trigger address_update_before;  // ERROR 1360 (HY000): Trigger does not exist

end //
delimiter ;

call drop_a_trigger();

There are two threads about this on the MySQL forums:

  • Drop statement in stored procedure
  • How to drop trigger in store procedure?

They both reach the same conclusion that even using a stored procedure will not help.


SELECT Concat('DROP TRIGGER ', Trigger_Name, ';') FROM  information_schema.TRIGGERS WHERE TRIGGER_SCHEMA = 'your_schema';

Copy and paste the generated sql


This is an old question, but since it's the one that keeps popping up in my searches I thought I'd post a solution here. In my case I needed to create a single file that had a full mysqldump, would then drop any triggers, and then re-add them all. I was able to do it by using the following command to append the DROP TRIGGER statements to my dump prior to appending the dump of the triggers.

mysql -u [db user] -p[db password] --skip-column-names [db name] -e 'SHOW TRIGGERS;' | cut -f1 | sed -r 's/(.*)/DROP TRIGGER IF EXISTS \1;/' >> dump.sql

To actually drop all the triggers in the same command (as mentioned by @Stephen Crosby in the comments), you can just pipe this back into MySQL like so:

mysql -u [db user] -p[db password] --skip-column-names [db name] -e 'SHOW TRIGGERS;' | cut -f1 | sed -r 's/(.*)/DROP TRIGGER IF EXISTS \1;/' | mysql -u [db user] -p[db password] [db name]

Tags:

Mysql

Triggers

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