MySQL trigger syntax schema

Question

MySQL trigger syntax schema

michaelirey opened this issue 10 years ago · comments

Everything was working great until..

rake db:reset

rake aborted!
Mysql2::Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '% TRIGGER

Was able to hunt the issue down and it turns out this was being generated in the schema.rb file:

  execute(<<-TRIGGERSQL)
CREATE DEFINER = root@% TRIGGER event_users_before_insert_row_tr BEFORE INSERT ON event_users
FOR EACH ROW
BEGIN
    SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);
END
  TRIGGERSQL

The fix is:

  execute(<<-TRIGGERSQL)
CREATE DEFINER = 'root'@'%' TRIGGER event_users_before_insert_row_tr BEFORE INSERT ON event_users
FOR EACH ROW
BEGIN
    SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);
END
  TRIGGERSQL

The only difference is putting quotes around the username and host. I checked the mysql documentation and found this:

http://dev.mysql.com/doc/refman/5.1/en/create-trigger.html

"The DEFINER clause specifies the MySQL account to be used when checking access privileges at trigger activation time. If a user value is given, it should be a MySQL account specified as 'user_name'@'host_name' (the same format used in the GRANT statement), CURRENT_USER, or CURRENT_USER(). The default DEFINER value is the user who executes the CREATE TRIGGER statement. This is the same as specifying DEFINER = CURRENT_USER explicitly."

Michael Irey · Answer 1 · Fri Apr 25 2014 03:30:01 GMT+0800 (China Standard Time)

I noticed even when I do:

trigger.security("'root'@'%'").before(:insert)

The quotes are striped out, I we end up with:

  execute(<<-TRIGGERSQL)
CREATE DEFINER = root@% TRIGGER event_users_before_insert_row_tr BEFORE INSERT ON event_users
FOR EACH ROW
BEGIN
    SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);
END
  TRIGGERSQL

Jon Jensen · Answer 2 · Fri Apr 25 2014 17:54:28 GMT+0800 (China Standard Time)

looks like it's due to how mysql returns the Definer when you call SHOW TRIGGERS ... even though you have to quote the user and host when creating a trigger, they are never quoted when you query the triggers from the db, e.g. you just get something like hairtrigger@localhost

so it should be pretty easy to make hairtrigger handle that correctly

that said, it is a little odd that your schema.rb is generating raw CREATE TRIGGER calls (instead of create_trigger). how were these triggers added to the db? model triggers with the rake task? manual create_trigger calls? or execute("CREATE TRIGGER...")?

Michael Irey · Answer 3 · Sat Apr 26 2014 05:48:00 GMT+0800 (China Standard Time)

They were added as model triggers with the rake task, as described in the documentation.

Let me know if you would like a code sample.

Michael Irey · Answer 4 · Sat Apr 26 2014 05:51:21 GMT+0800 (China Standard Time)

Come to think of it I did get this message in the schema.rb as well: " WARNING: generating adapter-specific definition for #{name} due to a mismatch. either there's a bug in hairtrigger or you've messed up your migrations and/or db :-/"

Jon Jensen · Answer 5 · Sat Apr 26 2014 05:56:37 GMT+0800 (China Standard Time)

that might be a symptom of the definer mismatch. so yeah, if you could send a sample of the model triggers you're using, that would help track it down and hopefully we can solve both problems at once

Michael Irey · Answer 6 · Sat Apr 26 2014 06:03:09 GMT+0800 (China Standard Time)

Here is the migration that was generated:

# This migration was auto-generated via `rake db:generate_trigger_migration'.
# While you can edit this file, any changes you make to the definitions here
# will be undone by the next auto-generated trigger migration.

class CreateTriggersEventUsersInsertAndEventUsersUpdate < ActiveRecord::Migration
  def up
    create_trigger("event_users_before_insert_row_tr", :generated => true, :compatibility => 1).
        on("event_users").
        before(:insert) do
      "SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);"
    end

    create_trigger("event_users_before_update_row_tr", :generated => true, :compatibility => 1).
        on("event_users").
        before(:update) do
      "SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);"
    end
  end

  def down
    drop_trigger("event_users_before_insert_row_tr", "event_users", :generated => true)

    drop_trigger("event_users_before_update_row_tr", "event_users", :generated => true)
  end
end

Michael Irey · Answer 7 · Sat Apr 26 2014 06:04:39 GMT+0800 (China Standard Time)

And here is a module included in our active record models:

module AutoCreatedUpdated

  extend ActiveSupport::Concern

  included do 

    @trigger_sql = "SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at)"

    trigger.before(:insert) { @trigger_sql } 
    trigger.before(:update) { @trigger_sql } 

  end

end

Michael Irey · Answer 8 · Sat Apr 26 2014 06:05:21 GMT+0800 (China Standard Time)

mysql version 5.1.70

Michael Irey · Answer 9 · Sat Apr 26 2014 06:07:43 GMT+0800 (China Standard Time)

Which created this in the schema.rb

# no candidate create_trigger statement could be found, creating an adapter-specific one
  execute(<<-TRIGGERSQL)
CREATE DEFINER = root@% TRIGGER event_users_before_insert_row_tr BEFORE INSERT ON event_users
FOR EACH ROW
BEGIN
    SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);
END
  TRIGGERSQL

  # no candidate create_trigger statement could be found, creating an adapter-specific one
  execute(<<-TRIGGERSQL)
CREATE DEFINER = root@% TRIGGER event_users_before_update_row_tr BEFORE UPDATE ON event_users
FOR EACH ROW
BEGIN
    SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);
END
  TRIGGERSQL

Michael Irey · Answer 10 · Sat Apr 26 2014 06:13:49 GMT+0800 (China Standard Time)

When we added this module to multiple models at the same time we got this:

  # WARNING: generating adapter-specific definition for event_notes_before_insert_row_tr due to a mismatch.
  # either there's a bug in hairtrigger or you've messed up your migrations and/or db :-/
  execute(<<-TRIGGERSQL)
CREATE DEFINER = root@% TRIGGER event_notes_before_insert_row_tr BEFORE INSERT ON event_notes
FOR EACH ROW
BEGIN
    SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), 
          NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);
END
  TRIGGERSQL

  # WARNING: generating adapter-specific definition for event_notes_before_update_row_tr due to a mismatch.
  # either there's a bug in hairtrigger or you've messed up your migrations and/or db :-/
  execute(<<-TRIGGERSQL)
CREATE DEFINER = root@% TRIGGER event_notes_before_update_row_tr BEFORE UPDATE ON event_notes
FOR EACH ROW
BEGIN
    SET NEW.created_at = IFNULL(NEW.created_at, NOW()), NEW.created_at = IF(NEW.created_at = '0000-00-00 00:00:00', NOW(), NEW.created_at), 
          NEW.updated_at = IFNULL(NEW.updated_at, NOW()), NEW.updated_at = IF(NEW.updated_at = '0000-00-00 00:00:00', NOW(), NEW.updated_at);
END
  TRIGGERSQL