feat(charset)!: utf8 is a new charset default and utf8_general_ci is a new collation default in the engine configuration file shipped
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Co-authored-by: Leonid Fedorov <leonid.fedorov@mariadb.com>
Co-authored-by: mariadb-DanielLee <daniel.lee@mariadb.com>
This patch improves handling of NULLs in textual fields in ColumnStore.
Previously empty strings were considered NULLs and it could be a problem
if data scheme allows for empty strings. It was also one of major
reasons of behavior difference between ColumnStore and other engines in
MariaDB family.
Also, this patch fixes some other bugs and incorrect behavior, for
example, incorrect comparison for "column <= ''" which evaluates to
constant True for all purposes before this patch.