You've already forked mariadb-columnstore-engine
mirror of
https://github.com/mariadb-corporation/mariadb-columnstore-engine.git
synced 2025-08-30 14:21:11 +03:00
5bcc1cd1f0
- MCOL-4527 Simple query performace is degraded between 5.4 and 5.5
xxx_nopad_bin collations are now around 30% faster on simple queries like:
SELECT * FROM t1 WHERE short_char_column_nopad_bin = 'literal'
The gain is achieved by comparing two short CHAR values as uint64_t.
Note, this patch does not affect xxx_bin collations!
It wouldn't be correct to apply the same improvement for xxx_bin
collations (i.e. with PAD SPACE attribute), because it would change
the way how trailing spaces are compared.
- MCOL-4539 WHERE short_char_column='literal' ignores the collation on a huge table
Only the first thread used a correct collation when performing:
WHERE short_char_char='literal'
Other (15) threads used the server default collation, because
the charsetNumber attribute was not copyed during cloning.
- This patch also adds mtr/basic/suite.opt, so "mtr" can run without --extern.