ApsaraDB for OceanBase:Truncate partitions

Syntax

truncate_partition_subpart:
TRUNCATE { partition_extended_names | subpartition_extended_names }
   [ { DROP [ ALL ] | REUSE } STORAGE ]
   [ update_index_clauses [ parallel_clause ] ] [ CASCADE ]

partition_extended_names:
{ PARTITION | PARTITIONS }
partition | { FOR ( partition_key_value [, partition_key_value ]... ) }
  [, partition | { FOR ( partition_key_value [, partition_key_value ]... ) } ]...

subpartition_extended_names:
{ SUBPARTITION | SUBPARTITIONS }
subpartition | { FOR ( subpartition_key_value [, subpartition_key_value ]... ) }
  [, subpartition | { FOR ( subpartition_key_value [, subpartition_key_value ]... ) } ]...

update_index_clauses:
{ { UPDATE | INVALIDATE } GLOBAL INDEXES
| UPDATE INDEXES
   [ ( index ( update_index_partition
             | update_index_subpartition
             )
        [, index ( update_index_partition
                 | update_index_subpartition
                 )
        ]...
      )
   ]
}

parallel_clause:
{ NOPARALLEL | PARALLEL [ integer ] }

Supported operations

• Dropping rows in a partition or subpartition by specifying the partition or subpartition name is supported. Sample code:

  ALTER TABLE T TRUNCATE PARTITION P0;
  ALTER TABLE T TRUNCATE PARTITIONS P0,P1;
  ALTER TABLE T TRUNCATE SUBPARTITION SP0;
  ALTER TABLE T TRUNCATE SUBPARTITIONS SP0,SP1;

• Updating indexes in a table by using the UPDATE GLOBAL INDEXES clause is supported.

Unsupported operations

Invalidating global indexes by using the INVALIDATE GLOBAL INDEXES clause is not supported. This clause will be converted into the UPDATE GLOBAL INDEXES clause.

Ignored clauses and options

• The UPDATE INDEXES clause.

• The CASCADE clause.

• The { DROP [ ALL ] | REUSE } STORAGE clause for releasing all storage space of a specified row.

• The parallel_clause clause for modifying the default query and DML parallelism for a table.

• The option for dropping rows in a partition by specifying the partition or subpartition key value.