Global Temporary Tables – Change in Oracle 12c

A few weeks back I was copied on an email conversation about a important change with Global Temporary Tables (GTT) in Oracle Database 12c.

Something you need to be aware of when using GTTs in Oracle Database 12.1.0.2:
Prior to this release GTTs shared statistics between sessions. Statistics were SHARED between different sessions. Now since Oracle Database 12c this is different by default – statistics on GTTs are visible to the SESSION only.

This can be changed and altered of course. And there are pros and cons. But as I’m not an optimizer expert I’m glad that my colleague Nigel Bayliss, our Optimizer Product Manager, has blogged about it. If you use this functionality please read all the details about this change here:

Thanks Nigel!

–Mike

PS: Original post said: Oracle Database 12.1.0.2 but I misread it – and thanks for the hint – it got introduced with Oracle Database 12.1.0.1 🙂

Share this: