Dear All:
I have done my test for 2 actions do simultaneously for the same command. Here is my approvement.
CORRECTION TABLE :
You need locking, not transactions. the problem is that both scripts load the initial version (ie with quantity = 10). when the second one completes it ignores the changes made by the first one.
Fred
Thanks my bro, fred. Here is my second experiment
Are you tables MyISAM? MyISAM tables don't support transactions or row level locks (AR's optimistic locking is probably a better fit for this anyway) so this would be entirely surprising (but using transactions is necessary for pessimistic locking; the lock is held for the duration of the current transaction
Fred
Yes it is ENGINE=MyISAM :((
How I can move it? I use SQLYOG and XAMP, it says ENGINE=MyISAM, MySQL GUI v5.14.
Thank you, Reinhart
set it to innodb. No idea what SQLYOG or XAMP are. Also I noticed that for some reason you're doing this from unit tests which (normally) destroy and reload the test database each time you run them
Fred
What is the best way to test it out of unit test? Thank you.
I cant find to convert MyISAM to InnoDB fast and safety. I have lot of table tobe converted, any suggestion?
Thanks, Reinhart
See the MySQL doc for ALTER TABLE
ALTER TABLE items ENGINE=INNODB
Not work, I use phpMyAdmin at XAMP and SQLYOG
script/runner for example or just require boot.rb and environment.rb
Fred