Installation of foreign keys

Installation of foreign keys

by Eric Richer -
Number of replies: 2

Good day folks, 

maybe I am missing something here but do foreign keys really not get installed in the database when Moodle is installed?

I see some keys defined in the install.xml files but they aren't present in the DB.  Maybe this is just an installation thing and a script needs to be run afterwards?

Cheers

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In reply to Eric Richer

Re: Installation of foreign keys

by Howard Miller -
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Historically, Moodle was developed with versions of MySQL that did not support foreign keys. I'm not completely sure what the status is now... I suspect very patchy.
In reply to Eric Richer

Re: Installation of foreign keys

by Marcus Green -
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You are not missing anything.  The Foreign Key information in the xml is discarded during installation along with field level comments. 

You can read more about it here

https://github.com/marcusgreen/moodle_local-sqlgenerator/wiki

And the results of my work on table relationships can be seen in this set of er diagrams 

https://www.examulator.com/er/output/relationships.html

and table descriptions.

https://www.examulator.com/er/output/index.html

The introduction page.

http://www.examulator.com/er

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