On an error (such as when an index cannot be dropped due to
FOREIGN KEY constraints), the field dict_index_t::to_be_dropped
was only being cleared in debug builds, even though the field
is available and being used also in non-debug builds.
This was a regression that was introduced by myself originally
in MySQL 5.7.6 and later merged to MariaDB 10.2.2, in
d39898de8e
An error manifested itself in the MariaDB Server 10.4 non-debug build,
involving instant ADD or DROP column. Because an earlier failed
ALTER TABLE operation incorrectly left the dict_index_t::to_be_dropped
flag set, the column pointers of the index fields would fail to be
adjusted for instant ADD or DROP column (MDEV-15562). The instant
ADD COLUMN in MariaDB Server 10.3 is unlikely to be affected by a
similar scenario, because dict_table_t::instant_add_column() in 10.3
is applying the transformations to all indexes, not skipping
to-be-dropped ones.
Make all system tables in mysql directory of type
engine=Aria
Privilege tables are using transactional=1
Statistical tables are using transactional=0, to allow them
to be quickly updated with low overhead.
Help tables are also using transactional=0 as these are only
updated at init time.
Other changes:
- Aria store engine is now a required engine
- Update comment for Aria tables to reflect their new usage
- Fixed that _ma_reset_trn_for_table() removes unlocked table
from transaction table list. This was needed to allow one
to lock and unlock system tables separately from other
tables, for example when reading a procedure from mysql.proc
- Don't give a warning when using transactional=1 for engines
that is using transactions. This is both logical and also
to avoid warnings/errors when doing an alter of a privilege
table to InnoDB.
- Don't abort on warnings from ALTER TABLE for changes that
would be accepted by CREATE TABLE.
- New created Aria transactional tables are marked as not movable
(as they include create_rename_lsn).
- bootstrap.test was changed to kill orignal server, as one
can't anymore have two servers started at same time on same
data directory and data files.
- Disable maria.small_blocksize as one can't anymore change
aria block size after system tables are created.
- Speed up creation of help tables by using lock tables.
- wsrep_sst_resync now also copies Aria redo logs.
remove remnants of 10.0 bugfix, incorrectly merged into 10.2
Using col_names[i] was obviously, wrong, must've been col_names[ifield->col_no].
incorrect column name resulted in innodb having index unique_id2(id1),
while the server thought it's unique_id2(id4).
But col_names[ifield->col_no] is wrong too, because `table` has non-renamed
columns, so the correct column name is always dict_table_get_col_name(table, ifield->col_no)
automatic shortening of a too-long non-unique key should
be not a warning, but a note. It's a normal optimization,
doesn't affect correctness, and should never be converted to
an error, no matter how strict sql_mode is.