Am 01.06.2017 um 14:07 schrieb Wetzel, Juergen (Juergen):
Am 31.05.2017 um 13:27 schrieb Wetzel, Juergen (Juergen):
Only 130 rows out of the 30000 have ARCHIVED = 0
in this case i would suggest a partial index:
create index <indexname> on <tablename> (archived) where archived = 0;
Thanks, Andreas.
Sorry for the confusion about the table names.
The hint with the partial index sounds as it could solve the problem. I will test it.
Hi,
I created now a partial index
create index on document (archived) where archived = '0';
just to be sure: this syntay is wrong, missing index-name. But it seems
the index is document_archived_idx ...
But result is same as before: a short like expression included in doubled %-signs leads to a fast query plan whereas a longer like expression or use of single %-sign creates a much slower query. Please see below query plans. Most surprisingly to me is the influence of the like expression, especially the doubled %-sign on short expressions. Any other ideas how to speed up that query or what is going on here in general?
please consider my plan B) and increase the stats. See my other mail.
Regards, Andreas
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