Update query planner statistics of database after library scan finished #4199
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Pull Request Test Coverage Report for Build 1133670393
💛 - Coveralls |
daschuer
reviewed
Aug 14, 2021
tools/mixxxdb_cleanup.sql
Outdated
| VACUUM; | ||
| -- Update statistics for the query planner | ||
| -- https://www.sqlite.org/lang_analyze.html | ||
| ANALYZE; |
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What is the rational for Analyze before Vacuum? I would swap it intuitively.
Can you add a comment?
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I don't know which order is correct and why to choose one over the other:
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Found it:
https://sqlite.org/forum/forumpost/62fb63a29c5f7810?t=h
Richard Hipp himself recommends to run VACCUM before ANALYZE.
Holzhaus
reviewed
Aug 15, 2021
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This operation turned out to be crucial for achieving an acceptable performance after a mass import into aoide. Otherwise some queries took 30-90s on a large library or just stalled at 100% CPU! Though the issue might not affect Mixxx which uses a simpler schema that requires less JOINs.
The operation typically finishes after ~5-10 sec.