diff --git a/gpdb-doc/dita/admin_guide/ddl/ddl-partition.xml b/gpdb-doc/dita/admin_guide/ddl/ddl-partition.xml index 831cf77bbb76c330ce1adf7c6ac956fc87a4d95b..c5f52bbb3ad59e3f15d1f469238f9a28e97ff550 100644 --- a/gpdb-doc/dita/admin_guide/ddl/ddl-partition.xml +++ b/gpdb-doc/dita/admin_guide/ddl/ddl-partition.xml @@ -5,9 +5,9 @@
Table partitioning enables supporting very large tables, such as fact tables, by logically dividing them into smaller, more manageable pieces. Partitioned tables can improve query - performance by allowing the Greenplum Database query optimizer to scan only the - data needed to satisfy a given query instead of scanning all the contents of a large table. -
Partitioning does not change the physical distribution of table data across the segments. - Table distribution is physical: Greenplum Database physically divides - partitioned tables and non-partitioned tables across segments to enable parallel query - processing. Table partitioning is logical: Greenplum Database logically - divides big tables to improve query performance and facilitate data warehouse maintenance - tasks, such as rolling old data out of the data warehouse.
+ Table distribution is physical: Greenplum Database physically divides partitioned tables and + non-partitioned tables across segments to enable parallel query processing. Table + partitioning is logical: Greenplum Database logically divides big tables to improve + query performance and facilitate data warehouse maintenance tasks, such as rolling old data + out of the data warehouse.Greenplum Database supports:
Greenplum Database divides tables into parts (also known as partitions) to
- enable massively parallel processing. Tables are partitioned during
Greenplum uses the partition criteria defined during table
- creation to create each partition with a distinct
The Greenplum system catalog stores partition hierarchy
- information so that rows inserted into the top-level parent table propagate correctly to the
- child table partitions. To change the partition design or table structure, alter the parent
- table using
Greenplum Database divides tables into parts (also known as partitions) to enable massively
+ parallel processing. Tables are partitioned during
Greenplum uses the partition criteria defined during table creation to create each
+ partition with a distinct
The Greenplum system catalog stores partition hierarchy information so that rows inserted
+ into the top-level parent table propagate correctly to the child table partitions. To change
+ the partition design or table structure, alter the parent table using
To insert data into a partitioned table, you specify the root partitioned table, the table
created with the
You can have Greenplum Database automatically generate partitions by giving
- a
You can have Greenplum Database automatically generate partitions by giving a
+
For more information about default partitions, see
GPORCA, the Greenplum next generation query optimizer, supports uniform multi-level partitioned tables. If GPORCA is enabled and the multi-level partitioned table is not uniform, Greenplum Database executes queries against the table with the legacy query +
GPORCA, the Greenplum next generation query optimizer, supports uniform multi-level
+ partitioned tables. If GPORCA is enabled and the multi-level partitioned table is not
+ uniform, Greenplum Database executes queries against the table with the legacy query
optimizer. For information about uniform multi-level partitioned tables, see
Exchanging a leaf child partition with an external table is not supported if the @@ -494,8 +495,8 @@ WHERE tablename='sales';
For information about Greenplum Database system catalog tables and views, - see the Greenplum Database Reference Guide.
+For information about Greenplum Database system catalog tables and views, see the + Greenplum Database Reference Guide.
If your partition design is multi-level, each level in the hierarchy - must have a default partition. For example:
+If your partition design is multi-level, each level in the hierarchy must have a default + partition. For example:
The Greenplum Database server configuration parameter
For information about the parameter, see "Server Configuration Parameters" in the
- Greenplum Database Reference Guide.
For information about exchanging and altering a leaf child partition, see the
-
For information about limitations of partitioned tables that contain a external table
partition, see