This changeset contains fixes in Oracle mode tests and for the
implementation of the CONCAT_ORACLE. Also, we harmonise our
translation process with the recent changes in the server.
Due to changed behavior of the server, some CREATE VIEW/EXPLAIN
statements' results begun to output unexpected results and need to be
fixed.
Also, concatenation operation's name also changed. This lead to
disabled func_concat_oracle test to be enabled to test it and it
turned out that our implementation of this function was broken
and need to be fixed too.
The idea is relatively simple - encode prefixes of collated strings as
integers and use them to compute extents' ranges. Then we can eliminate
extents with strings.
The actual patch does have all the code there but miss one important
step: we do not keep collation index, we keep charset index. Because of
this, some of the tests in the bugfix suite fail and thus main
functionality is turned off.
The reason of this patch to be put into PR at all is that it contains
changes that made CHAR/VARCHAR columns unsigned. This change is needed in
vectorization work.
* 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* Fix ISO C++17 does not allow 'register' storage class specifier for outdated bison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
