Confluence MySQL Database indexes

[Dominic Baines]

I am working on a client site where they have an old version of confluence (functionality is fine does what they want it to) and newer version. V2.7 and V4.

Sometimes the users moan that the system is running slower than expected... it is running but there are some non-performing queries running on the database. The newer system is not seeing the issues so I did a schema comparison and aside from a few tabl;e differences that are for functionality purposes the major difference I can see are the ealier version is missing a lot of the indexes I would create on the MySQL (5.077) schema.

Question is this... will it cause irreperable harm to any potential update option if I were to add the indexes that I can see are 'missing', I can easily create the appropriate drop statements so that they could be removed if needed.

Interested to hear views.

Dom

[William Zanchet [Atlassian] · Accepted solution]

Hi Dom,

If you're planing to upgrade your Confluence all the way to 4 series. I highly suggest you to follow an upgrade path: 2.7 > 3.5.17 > 4 series. It's not reliable to jump directly to 4 series, because that can lead us to several problems.

Cheers,

WZ

[Dominic Baines]

Absolutely.... I am not planning on upgrading. I have a client (I am a contractor) that does not wish to pay for the upgrade but that doesn't stop them moaning about performance of the older application. A check in the database shows a lot of the expected indexes or recommended ones are just not there in the earlier schema so I was asking what the issues might be.

[Nic Brough -Adaptavist-]

I've done that a couple of times. It's completely harmless, with the caveat you have already mentioned.

When upgrading in place (pointing a 3.1 Confluence at a database that was behind a 2.9 installation), it fell over on the new indices. A real DBA did give me an explanation at the time, but all I can remember was that if we dropped the indices we'd added before starting the 3.1 installation, it all worked perfectly. I seem to remember her saying that the problem was with (re)creating an index that we'd already added by hand, and we didn't need to drop it that if our user had more permissions, but don't quote me.