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Thank you for your contribution! This is a preliminary review.
One general note on the commit message: please do not summarize the changes done.
Good commit messages usually follow the following pattern:
- what was wrong exactly
- how it was fixed
- how was the fix tested.
Item_cache_int::val_real() converts the stored integer to DOUBLE as a signed value even when unsigned_flag is set. Values above LLONG_MAX therefore become negative. A BETWEEN comparison using a cached ~TRUE bound can then discard a row that should match an IS FALSE predicate. Interpret unsigned cached bits as ulonglong before converting to DOUBLE, using unsigned_flag to select the correct conversion. Add a BETWEEN query with a bitwise complement and a VARCHAR column to func_bit. Use two rows so constant-table optimization cannot bypass the cache. Check that zero lies below the unsigned lower bound for both rows. Bug report: https://jira.mariadb.org/browse/MDEV-40089
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LGTM. Thanks! Please stand by for the final review.
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Item_cache_int::val_real() interprets stored unsigned bits as a signed integer before converting to DOUBLE. Values above LLONG_MAX become negative, so a BETWEEN predicate using a cached ~TRUE bound can wrongly discard rows.
Use unsigned_flag to convert unsigned cached values through ulonglong before converting to DOUBLE.
Regression coverage
Add one query to
main.func_bitwith a bitwise complement and a VARCHAR column. Two rows prevent constant-table optimization from bypassing the cache. Both should satisfy IS FALSE because zero is below the unsigned lower bound; ORDER BY makes the result deterministic.The five-line test needs no InnoDB prerequisite, SET, database creation, manual prepared statements or duplicate queries. Existing test prerequisites remain unchanged, and MTR supplies prepared-statement and view protocol coverage.
Validation
On current
11.4atf49e838d367f2154b3edb43effa99ff9eb0d8602:main.func_bitonly on the new query, returning no rows instead of0and1.main.func_bit,main.select,main.type_bit,main.type_bit_innodb,main.type_decimalandmain.type_floatpass.main.func_bitpasses.main.func_bitpasses.Bug report: https://jira.mariadb.org/browse/MDEV-40089