Extended keys works by first checking if the engine supports extended
keys.
If yes, it extends secondary key with primary key components and mark the
secondary keys as HA_EXT_NOSAME (unique).
If we later notice that there where no primary key, the extended key
information for secondary keys in share->key_info is reset. However the
key_info->flag HA_EXT_NOSAME was not reset!
This causes some strange things to happen:
- Tables that have no primary key or secondary index that contained the
primary key would be wrongly optimized as the secondary key could be
thought to be unique when it was not and not unique when it was.
- The problem was not shown in EXPLAIN because of a bug in
create_ref_for_key() that caused EQ_REF to be displayed by EXPLAIN as REF
when extended keys where used and the secondary key contained the primary
key.
This is fixed with:
- Removed wrong test in make_join_select() which did not detect that key
where unique when a secondary key contains the primary.
- Moved initialization of extended keys from create_key_infos() to
init_from_binary_frm_image() after we know if there is a usable primary
key or not. One disadvantage with this approach is that
key_info->key_parts may have not used slots (for keys we thought could
be extended but could not). Fixed by adding a check for unused key_parts
to copy_keys_from_share().
Other things:
- Simplified copying of first key part in create_key_infos().
- Added a lot of code comments in code that I had to check as part of
finding the issue.
- Fixed some indentation.
- Replaced a couple of looks using references to pointers in C
context where the reference does not give any benefit.
- Updated Aria and Maria to not assume the all key_info->rec_per_key
are in one memory block (this could happen when using dervived
tables with many keys).
- Fixed a bug where key_info->rec_per_key where not allocated
- Optimized TABLE::add_tmp_key() to only call alloc() once.
(No logic changes)
Test case changes:
- innodb_mysql.test changed index as an index the optimizer thought
was unique, was not. (Table had no primary key)
TODO:
- Move code that checks for partial or too long keys to the primary loop
earlier that initally decides if we should add extended key fields.
This is needed to ensure that HA_EXT_NOSAME is not set for partial or
too long keys. It will also shorten the current code notable.
The MDEV-25004 test innodb_fts.versioning is omitted because ever since
commit 685d958e38 InnoDB would not allow
writes to a database where the redo log file ib_logfile0 is missing.
Works like vers_force but forces trx_id-based system-versioned tables
if the storage supports it (currently InnoDB-only). Otherwise creates
timestamp-based system-versioned table.
mysql_discard_or_import_tablespace(): On successful
ALTER TABLE...DISCARD TABLESPACE, evict the table handle from the
table definition cache, so that ha_innobase::close() will be invoked,
like InnoDB expects to be the case. This will avoid an assertion failure
ut_a(table->get_ref_count() == 0) during IMPORT TABLESPACE.
ha_innobase::open(): Do not issue any ER_TABLESPACE_DISCARDED warning.
Member functions for DML will do that.
ha_innobase::truncate(), ha_innobase::check_if_supported_inplace_alter():
Issue ER_TABLESPACE_DISCARDED warnings, to compensate for the removal of
the warning in ha_innobase::open().
row_quiesce_write_indexes(): Only write information about committed
indexes. The ALTER TABLE t NOWAIT ADD INDEX(c) in the nondeterministic
test case will most of the time fail due to a metadata lock (MDL) timeout
and leave behind an uncommitted index.
Reviewed by: Sergei Golubchik
Like in MDEV-16110 we must release items allocated on thd->mem_root by
reopening the table.
MDEV-16290 relocated MDEV-16110 fix in 10.5 so it works for MDEV-28576
as well. 10.3 without MDEV-16290 now duplicates this fix.
Fix the regression introduced in
dfb41fddf6.
In the restructure of mysql_rm_table_no_locks the early condition
of !frm_error that enabled non_tmp_table_deleted, and hence the
query cache invalidation, was removed.
The query_cache_invalidate1(thd, dbnorm) called after
mysql_rm_table_no_locks depends on the query cache removal
(for unexamined reasons).
Under DROP DATABASE, in mysql_rm_table_no_locks, dont_log_query
is true preventing the late setting of non_tmp_table_deleted
(which retained one of its purposes as a replication deletion
of temporary tables, but not query cache invalidation).
The non_temp_tables_count however can still be used to invalidate
the query cache.
For commands
(1) alter table t1 add partition (partition p2);
(2) alter table t1 add partition (partition px history);
It printed the same error message:
Wrong partitioning type, expected type: `SYSTEM_TIME`
For (1) it is not clear from the syntax that we are trying to add
HASH partition. For (2) it is not clear that the table partitioning is
different than SYSTEM_TIME. Now it prints what type we are trying to
add to what type of partitioning.
Fixed warning unused function rename_field_in_list() for compilation
without partitioning.
