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DDL for Partitioned Tables

The mechanism used for DDL operations on partitioned tables is somewhat different from the online

DDL discussed throughout this section. The partitioning clauses of the

alter table statement

are only allowed in conjunction with algorithm=default and lock=default. Although these

operations do not go through the same internal online DDL API as for non-partitioned tables, MySQL

still attempts to minimize data copying and locking where possible:

•add partition and drop partition for ta bies partitioned by rangę or list do not copy any existing data.

•    truncate partition does not copy any existing data, for all types of partitioned tables.

•    Concurrent queries are allowed during add partition and coalesce partition for tables

partitioned by hash or list. MySQL copies the data while holding a shared lock.

•    ForREORGANIZE PARTITION, REBUILD PARTITION, OrADD PARTITION orCOALESCE

partition for a table partitioned by linear hash or list, concurrent queries are allowed. Data

from the affected partitions is copied while holding a shared lock.