https://deltanine.net/mw/index.php?action=history&feed=atom&title=MySQL_InnoDB_Foreign_Key_ErrorMySQL InnoDB Foreign Key Error - Revision history2026-04-27T19:10:57ZRevision history for this page on the wikiMediaWiki 1.32.1https://deltanine.net/mw/index.php?title=MySQL_InnoDB_Foreign_Key_Error&diff=667&oldid=prevChris: 1 revision2013-07-25T08:08:13Z<p>1 revision</p>
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</td></tr></table>Chrishttps://deltanine.net/mw/index.php?title=MySQL_InnoDB_Foreign_Key_Error&diff=666&oldid=prevChris at 09:35, 3 August 20092009-08-03T09:35:37Z<p></p>
<p><b>New page</b></p><div>I was getting Error 1005 "can't create table" ... errno 150 when trying to create a foreign key using the following<br />
<pre><br />
ALTER TABLE `user`<br />
ADD CONSTRAINT FOREIGN KEY (`group_id`) REFERENCES `group` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION;<br />
</pre><br />
<br />
What I needed to do to fix it was to create an index on group_id in the user table. Also if you get error 1452 make sure you don't already have fields filled which would otherwise be invalid.<br />
<br />
==Delete a Foreign Key==<br />
Get the Key Name from the bottom of an export, then<br />
<pre><br />
ALTER TABLE page_titles DROP FOREIGN KEY 0_172<br />
</pre></div>Chris