That's against 10k records in said table. I'll see about constructing a minimal test case. But sadly now, as I've "insert into ... direct ... select * from ...; " then I have to press on with my day job.
Do let me know if you have any ideas. Rich On Monday, 25 February 2019 15:36:15 UTC, Rich B wrote: > > Hi Noel > > I used the trace.db output facility and got this: > > alter table receipt drop primary key; >> alter table receipt alter column id identity not null; >> COMMIT; >> ----------------------------------------- >> -- SQL Statement Statistics >> -- time: total time in milliseconds (accumulated) >> -- count: how many times the statement ran >> -- result: total update count or row count >> ----------------------------------------- >> -- self accu time count result sql >> -- 100% 100% 47505 1 0 alter table receipt alter column id >> identity not null; >> -- 0% 100% 0 1 0 COMMIT; >> -- 0% 100% 0 1 0 alter table receipt drop primary key; >> >> > There's no triggers, custom table enginers, views etc. It's a really > simply setup. > > Cheers > Rich > > > > On Monday, 25 February 2019 14:43:48 UTC, Noel Grandin wrote: >> >> That doesn't make any sense. I do similar transformations all the time, >> and their running time is always roughly O(n). >> >> H2 basically builds a new table with new data, and then drops the old >> table and replaces it with the new. >> >> I suspect you have some other code getting in the way somehow (e.g. >> triggers, custom table engines, views, etc) >> >> Try using some performance profiler to see where the time is going (e.g. >> the very basic one built into H2 should be fine >> for this job). >> >> If that doesn't point you in the right direction, please construct a >> minimal test case, and log a bug. >> >> -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/d/optout.
