Better adaptive granularity calculation for wide parts#18223
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fortunately, catch check works. |
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Stress test failures are not related to changes. |
CurtizJ
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azat
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In ClickHouse#17120 (that was reverted in ClickHouse#17918 already) marks adjustemnt was introduced, but it may lead to corruption of marks files, that may cause two things: 1) Incorrect marks files, which lead to reading more rows than there are (can be reproduced with `max_threads`>1 or/and `PREWHERE`, and `optimize_move_to_prewhere`) 2) Can't adjust last granule because it has X rows, but try to subtract Y rows (ClickHouse#9260) And 1) is pretty hard to diagnosis, since it does not throw any error, it just may return wrong result. Fortunately both problems can be fixed with `OPTIMIZE TABLE ... [ FINAL]`. Cc: @alesapin Refs: ClickHouse#17943 Refs: ClickHouse#18223
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Make better adaptive granularity calculation for merge tree wide parts.