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.
* Fix clang warnings
* Remove vim tab guides
* initialize variables
* 'strncpy' output truncated before terminating nul copying as many bytes from a string as its length
* Fix ISO C++17 does not allow 'register' storage class specifier for outdated bison
* chars are unsigned on ARM, having if (ival < 0) always false
* chars are unsigned by default on ARM and comparison with -1 if always true
This fixes hex() so that it outputs the hex of the ASCII for the time
data to make it aligned with MariaDB. It also fixes the following
functions so that they use NOW() as a DATETIME with the input TIME added
to it:
* weekday()
* yearweek()
* monthname()
* last_day()
* year()
* weekofyear()
* week()
* to_days()
* quarter()
* month()
* dayofyear()
* dayofweek()
* dayofmonth()
* day()
* date()
For the initial BLOB/TEXT pull request we put them in the same bucket as
VARBINARY, forcing many functions to be disabled. This patch enables the
same TEXT function support as VARCHAR.
* TEXT and BLOB now have separate identifiers internally
* TEXT columns are identified as such in system catalog
* cpimport only requires hex input for BLOB, not TEXT
