@Martin: The issue you mention where never release; hence, I do not think they play a role, here. @Andreas: Most important question: Which version of MonetDB did work fine before, and which does no longer after the upgrade? For the new version, you could profile your quer(y|ies) by prefixing them with TRACE --- feel free to share the results for analysis --- unfortunately, you cannot (easily) downgrade to the older version to also profile that one. Would you be to share all ingredients to reproduce the problem? Also, do I understand correctly that you tested the alternative omitting LOWER() and using ILIKE, instead, and that works fine (also) with the new version of MonetDB? If so, you might also want to profile (TRACE) that one to compare the trace with that of the "slow" query. Best, Stefan ----- On Feb 24, 2016, at 9:43 PM, Martin martin.kersten@cwi.nl wrote:
Hi,
You can check the merovingian.log file for WARNINGs In the development branch 'default' we had a temporary bug that failed to find some bulk-operations. It has been fixed already. Perhaps you hit this jackpot.
regards, Martin
On 24/02/16 21:38, Andreas F. Hoffmann wrote:
Hello List,
I'm running monetdb on a Debian server and the software is managed via Debian packages. A few days ago I installed an update for the monetdb5-server package. After that I noticed a problem with queries with the function lower() in the WHERE clause:
WHERE LOWER(“fieldname”) LIKE '%lower_string%'<<
without any change to the data, the requests became much, much slower then before (from some hundred microseconds to some minutes). Not only in my application but also in the monetdb client...
I could solve the problem via a switch from using LIKE to ILIKE and no lower()-function, but I'm curious what could be the cause for this dramatic performance breakdown? I searched the release history but I found nothing...
Has anybody experienced the same effect? Anny ideas on this phenomenon?
Greetings from Germany, Andreas (theafh) _______________________________________________ users-list mailing list users-list@monetdb.org https://www.monetdb.org/mailman/listinfo/users-list
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