In MySQL 9.1, concurrent DDL is permitted on the
donor by default. Concurrent DDL support on the donor is
controlled by the
clone_block_ddl
variable.
Concurrent DDL support can be enabled and disabled dynamically
using a SET
statement like this
one:
SET GLOBAL clone_block_ddl={OFF|ON}
The default setting is
clone_block_ddl=OFF
, which
permits concurrent DDL on the donor.
Whether the effect of a concurrent DDL operation is cloned or not depends on whether the DDL operation finishes before the dynamic snapshot is taken by the cloning operation.
DDL operations that are not permitted during a cloning operation
regardless of the
clone_block_ddl
setting
include:
ALTER TABLE
tbl_name
DISCARD TABLESPACE;ALTER TABLE
tbl_name
IMPORT TABLESPACE;ALTER INSTANCE DISABLE INNODB REDO_LOG;