Mysql triggers with django

[Marc Aymerich]

Hello,

Is possible to implement mysql triggers with django?? there are some documentation about it? 

Thanks!!

Marc

[Marc Aymerich]

well, I found this one. 

http://www.eflorenzano.com/blog/post/database-triggers-arent-evil-and-they-actually-kin/

 

I've tried to implement something like that in mysql with my model but I get this error:

_mysql_exceptions.ProgrammingError: (2014, "Commands out of sync; you can't run this command now")

this is my implementation:

from django.db.models import signals

from ucp.panel import models

sql = """

DROP TRIGGER IF EXISTS new_domain;

CREATE TRIGGER new_domain BEFORE INSERT ON panel_domain

FOR EACH ROW 

BEGIN

DECLARE service integer;

IF ( NEW.hosted ) THEN

SET @domain = SUBSTRING(LCASE(NEW.name),'.',-1);

SET @domain = CONCAT('domain',@domain);

SELECT service_id INTO service FROM panel_service WHERE specific_data=@domain;

INSERT INTO panel_order (service, member, description, included, discount, discharge_date, cessation_date) VALUES(@service,NEW.member_id,NEW.name,0,0,CURTIME(),CURTIME());

END IF;

END;

"""

def create_trigger(app, created_models, verbosity, **kwargs):

    from django.db import connection

    cursor = connection.cursor()

    cursor.execute(sql)

signals.post_syncdb.connect(create_trigger, sender=models)

any idea¿¿

thanks!

Marc.

Traceback (most recent call last):

  File "manage.py", line 11, in <module>

    execute_manager(settings)

  File "/usr/lib/pymodules/python2.6/django/core/management/__init__.py", line 362, in execute_manager

    utility.execute()

  File "/usr/lib/pymodules/python2.6/django/core/management/__init__.py", line 303, in execute

    self.fetch_command(subcommand).run_from_argv(self.argv)

  File "/usr/lib/pymodules/python2.6/django/core/management/base.py", line 195, in run_from_argv

    self.execute(*args, **options.__dict__)

  File "/usr/lib/pymodules/python2.6/django/core/management/base.py", line 222, in execute

    output = self.handle(*args, **options)

  File "/usr/lib/pymodules/python2.6/django/core/management/base.py", line 351, in handle

    return self.handle_noargs(**options)

  File "/usr/lib/pymodules/python2.6/django/core/management/commands/syncdb.py", line 99, in handle_noargs

    emit_post_sync_signal(created_models, verbosity, interactive)

  File "/usr/lib/pymodules/python2.6/django/core/management/sql.py", line 205, in emit_post_sync_signal

    interactive=interactive)

  File "/usr/lib/pymodules/python2.6/django/dispatch/dispatcher.py", line 166, in send

    response = receiver(signal=self, sender=sender, **named)

  File "/var/www/ucp/../ucp/panel/management.py", line 24, in create_trigger

    cursor.execute(sql)

  File "/usr/lib/pymodules/python2.6/django/db/backends/util.py", line 19, in execute

    return self.cursor.execute(sql, params)

  File "/usr/lib/pymodules/python2.6/django/db/backends/mysql/base.py", line 84, in execute

    return self.cursor.execute(query, args)

  File "/usr/lib/pymodules/python2.6/MySQLdb/cursors.py", line 168, in execute

    if not self._defer_warnings: self._warning_check()

  File "/usr/lib/pymodules/python2.6/MySQLdb/cursors.py", line 75, in _warning_check

    warnings = self._get_db().show_warnings()

  File "/usr/lib/pymodules/python2.6/MySQLdb/connections.py", line 300, in show_warnings

    self.query("SHOW WARNINGS")

_mysql_exceptions.ProgrammingError: (2014, "Commands out of sync; you can't run this command now")

[Marc Aymerich]

I get this warning when I execute a syncdb ('python manage.py syncdb'). Python creates all tables, auth system creates superuser .. and then.. appears this warning. ¿is there something wrong? Because now I see that the trigger is created in the database.