dropping/creating tables".
The bug could lead to a crash when multi-delete statements were
prepared and used with temporary tables.
The bug was caused by lack of clean-up of multi-delete tables before
re-execution of a prepared statement. In a statement like
DELETE t1 FROM t1, t2 WHERE ... the first table list (t1) is
moved to lex->auxilliary_table_list and excluded from lex->query_tables
or select_lex->tables. Thus it was unaccessible to reinit_stmt_before_use
and not cleaned up before re-execution of a prepared statement.
An UNIQUE KEY consisting of NOT NULL columns
was displayed as PRIMARY KEY in "DESC t1".
According to the code, that was intentional
behaviour for some reasons unknown to me.
This code was written before bitkeeper time,
so I cannot check who and why made this.
After discussing on dev-public, a decision
was made to remove this code
table.cc:
Fixing to use system_charset_info instead of default_charset_info.
Crash happened because the "ctype" array is empty in UCS2,
and thus cannot be used with my_isspace().
The reason why UCS2 appeared in this context was because of
of default_charset_info variable incorrectly substituted to my_isspace().
As functions check_db_name(), check_table_name() and check_column_name()
always get values in utf8, system_charset_info must be used instead.
ctype_ucs2_def.test, ctype_ucs2_def-master.opt, ctype_ucs2_def.result:
new file
CREATE TABLE and PS/SP": make sure that 'typelib' object for
ENUM values and 'Item_string' object for DEFAULT clause are
created in the statement memory root.
After review version.
Added a condition for MERGE tables. These do not have unique
indexes. But every key could be a unique key on the underlying
MyISAM table. So get the maximum key length for MERGE tables
instead of the maximum unique key length. This is used for
buffer allocation in write_record().
Added a test case for bug #7520.
table.cc:
Fixed bug #7520.
The bug was caused by a wrong calculation of the field max_key_length for
a TABLE structure when there was an index on a blob field.
Now thd->mem_root is a pointer to thd->main_mem_root and THR_MALLOC is a pointer to thd->mem_root.
This gives us the following benefits:
- Allow us to easily detect if arena has already been swapped before (this fixes a bug in setup_conds() where arena was swaped twice in some cases)
- Faster swaps of arenas (as we don't have to copy the whole MEM_ROOT)
- We don't anymore have to call my_pthread_setspecific_ptr(THR_MALLOC,...) to change where memory is alloced. Now it's enough to set thd->mem_root
more logical table/index_flags
return HA_ERR_WRONG_COMMAND instead of abstract methods where appropriate
max_keys and other limits renamed to max_supported_keys/etc
max_keys/etc are now wrappers to max_supported_keys/etc
ha_index_init/ha_rnd_init/ha_index_end/ha_rnd_end are now wrappers to real {index,rnd}_{init,end} to enforce strict pairing
Actually it is not a bug but right behavior observed as pefomance
degradation after we have forced Item_field::fix_fields() to
re-execute each time when we are executing prep stmt.
This patch implements small optimization which heals this bad
behavior. We are caching field position in TABLE::field array in
Item's member and are using this position for speeding up field
lookups in fix_fields() in case of its re-execution.
