InnoDB does not allow creating multiple FULLTEXT INDEX
in ALGORITHM=INPLACE. This constraint was not being properly
enforced after MariaDB started to support ALGORITHM=INSTANT
and instant ADD COLUMN.
As a side effect of this bug, we again allow ALGORITHM=INPLACE
to rebuild a table when one FULLTEXT INDEX survives.
Also, we are returning a more accurate reason for refusing LOCK=NONE.
innobase_fulltext_exist(): Return the number of fulltext indexes.
ha_innobase::check_if_supported_inplace_alter(): If the table
needs to be rebuilt, refuse the operation if multiple fulltext
indexes would remain.
Introduced new alter algorithm type called NOCOPY & INSTANT for
inplace alter operation.
NOCOPY - Algorithm refuses any alter operation that would
rebuild the clustered index. It is a subset of INPLACE algorithm.
INSTANT - Algorithm allow any alter operation that would
modify only meta data. It is a subset of NOCOPY algorithm.
Introduce new variable called alter_algorithm. The values are
DEFAULT(0), COPY(1), INPLACE(2), NOCOPY(3), INSTANT(4)
Message to deprecate old_alter_table variable and make it alias
for alter_algorithm variable.
alter_algorithm variable for slave is always set to default.
- Inplace alter shouldn't support if the number of newly added fts index
exceeds 1 even though the table undergoes rebuild. It is a regression of
MDEV-14016
MariaDB inherits the MySQL limitation that ALGORITHM=INPLACE cannot
create more than one FULLTEXT INDEX at a time. As part of the MDEV-11369
Instant ADD COLUMN refactoring, MariaDB 10.3.2 accidentally stopped
enforcing the restriction.
Actually, it is a bug in MySQL 5.6 and MariaDB 10.0 that an ALTER TABLE
statement with multiple ADD FULLTEXT INDEX but without explicit
ALGORITHM=INPLACE would return in an error message, rather than
executing the operation with ALGORITHM=COPY.
ha_innobase::check_if_supported_inplace_alter(): Enforce the restriction
on multiple FULLTEXT INDEX.
prepare_inplace_alter_table_dict(): Replace some code with debug
assertions. A "goto error_handled" at this point would result in
another error, because the reference count of ctx->new_table would be 0.
