On 4 June 2018 at 06:08, Pavel Stehule <pavel.steh...@gmail.com> wrote:
> 4. optimization expression without necessity to create snapshots - > experiments > > @4 There are lot of not database expressions in PLpgSQL - like var1 := var1 > + var2 or var1 := var1 + konst. Own calculation needs about 1% of time of > total expression evaluation time. Almost all time get preparing plan cache, > preparing snapshot, .. For this case, when no database object is used, we > don't need use this infrastructure. I would to measure performance impact, > and testing if these optimizations are interesting or not. Sounds good. I think this would need to be restricted by operator and datatype, since in general you won't know if the datatype functions need a snapshot or not. Immutable functions for the operators ought to do it, but I think that might not be enough. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
