1. Adding a separate MY_COLLATION_HANDLER
my_collation_ucs2_general_mysql500_ci_handler
implementing a proper order for ucs2_general_mysql500_ci
The problem happened because ucs2_general_mysql500_ci
erroneously used my_collation_ucs2_general_ci_handler.
2. Cosmetic changes: Renaming:
- plane00_mysql500 to my_unicase_mysql500_page00
- my_unicase_pages_mysql500 to my_unicase_mysql500_pages
to use the same naming style with:
- my_unicase_default_page00
- my_unicase_defaul_pages
3. Moving code fragments from
- handler::check_collation_compatibility() in handler.cc
- upgrade_collation() in table.cc
into new methods in class Charset, to reuse the code easier.
This patch ensures that all identical character sets shares the same
cs->csname.
This allows us to replace strcmp() in my_charset_same() with comparisons
of pointers. This fixes a long standing performance issue that could cause
as strcmp() for every item sent trough the protocol class to the end user.
One consequence of this patch is that we don't allow one to add a character
definition in the Index.xml file that changes the csname of an existing
character set. This is by design as changing character set names of existing
ones is extremely dangerous, especially as some storage engines just records
character set numbers.
As we now have a hash over character set's csname, we can in the future
use that for faster access to a specific character set. This could be done
by changing the hash to non unique and use the hash to find the next
character set with same csname.
Replacing the slow loop in my_hash_sort_utf8mbX() to the fast
skip_trailing_spaces(), which consumes 8 bytes in one iteration,
and is around 8 times faster on long data.
Also, renaming:
- my_hash_sort_utf8() to my_hash_sort_utf8mb3()
- my_hash_sort_utf8_nopad() to my_hash_sort_utf8mb3_nopad()
to merge to 10.5 easier (automatically?).
The code did not take into account that:
- U+005C (backslash) can occupy more than mbminlen characters (e.g. in sjis)
- Some character sets do not have a code for U+005C (e.g. swe7)
Adding a new function my_wc_to_printable into MY_CHARSET_HANDLER to
cover all special cases easier.
main.derived_cond_pushdown: Move all 10.3 tests to the end,
trim trailing white space, and add an "End of 10.3 tests" marker.
Add --sorted_result to tests where the ordering is not deterministic.
main.win_percentile: Add --sorted_result to tests where the
ordering is no longer deterministic.
Synchronizing sources in:
- my_wildcmp_uca_impl() handling utf8_unicode_ci
- my_wildcmp_unicode_impl() handling utf8_general_ci
The latter has already had a fix for a similar MySQL bug in utf8_general_ci:
Bug#11754 SET NAMES utf8 followed by SELECT "A\\" LIKE "A\\" returns 0
So fix is now propagated to utf8_unicode_ci.
After the MDEV-13118 fix there's no code in the server that
wants caseup/casedn to change the argument in place for simple
charsets. Let's remove this logic and always return the result in a
new string for all charsets, both simple and complex.
1. Removing the optimization that *some* character sets used in casedn()
and caseup(), which allowed (and required) to change the case in-place,
overwriting the string passed as the "src" argument.
Now all CHARSET_INFO's work in the same way:
non of them change the source string in-place, all of them now convert
case from the source string to the destination string, leaving
the source string untouched.
2. Adding "const" qualifier to the "char *src" parameter
to caseup() and casedn().
3. Removing duplicate implementations in ctype-mb.c.
Now both caseup() and casedn() implementations for all CJK character sets
use internally the same function my_casefold_mb()
(the former my_casefold_mb_varlen()).
4. Removing the "unused" attribute from parameters of some my_case{up|dn}_xxx()
implementations, as the affected parameters are now *used* in the code.
Previously these parameters were used only in DBUG_ASSERT().
Do not silence uncertain cases, or fix any bugs.
The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.
Do not silence uncertain cases, or fix any bugs.
The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.
