Re: [firebird-support] Re: Best way to delete millions of rows

23.11.2016 9:06, Norbert Saint Georges n...@tetrasys.eu [firebird-support] wrote: > For tables of several hundred millions of recordings, if we organize > the first eight bytes in a less cahotic way, this will lighten Firebird > by making it faster? Yes, that's why sequential GUID was

Re: [firebird-support] Re: Best way to delete millions of rows

22.11.2016 21:01, 'Leyne, Sean' s...@broadviewsoftware.com [firebird-support] wrote: >> There would be a lot of advantage, for Firebird, in using this kind of guid? > > Yes, Firebird indexes use prefix compression so the leading 14 chars of the > above values > would be stored under a single

RE: [firebird-support] Re: Best way to delete millions of rows

> > @Ann > > I will run some test and see what happens if the guids are generated > > in way where the last part varies. Like this: > > 39db9ec6-178e-77b4-5d7b-d4e969b0cd98 > > 39db9ec6-178e-e4ba-54ed-92347a131663 > > 39db9ec6-178e-c95b-c709-a42e349410df > > There would be a lot of advantage, for

Re: [firebird-support] Re: Best way to delete millions of rows

On Nov 22, 2016, at 6:56 AM, kragh.tho...@yahoo.com [firebird-support] wrote: > > Pagesize is 16384 and pagebuffers is 256. Servermode is superclassic. > If I drop the primary key/index everything works as expected. > Interesting. GUIDs produce really fat

Re: [firebird-support] Re: Best way to delete millions of rows

Hi,   i agree with you   i suppose that time spend by GC should be measured and if it take to much time then stop GC and try again leter. E.g. when i do delete from milions_table and then do SELECT COUNT(*) form milions_table it should not clear whole garbages and stop query until GC finished.

Re: [firebird-support] Re: Best way to delete millions of rows

---In firebird-support@yahoogroups.com, wrote : >> Here you delete some records, but then count whole table. >>Add same "where" condition as in "count" query > > I think the execution of select count is for garbage collection. Sure > If count of records that does not exists is

Re: [firebird-support] Re: Best way to delete millions of rows

> > Here you delete some records, but then count whole table. > Add same "where" condition as in "count" query > > Regards, > Vlad I think the execution of select count is for garbage collection. If count of records that does not exists is executed, will be the garbage collection executed for