This topic describes how to use the SHOW COLUMNAR INDEX statement to query Clustered Columnar Indexes (CCIs) that have been created or are being created.
Usage notes
The version of your PolarDB-X instance is 5.4.19-16989811 or later.
Syntax
SHOW COLUMNAR {INDEX | INDEXES} [FROM [schema_name.]tbl_name]schema_name and tbl_name are optional parameters. These parameters are used to filter table names or query information about tables on other databases.
Sample statements:
SHOW COLUMNAR INDEX; # Query the CCIs of all tables on the current database
SHOW COLUMNAR INDEX FROM xxx_tb; # Query the CCIs of the xxx_tb table on the current database
SHOW COLUMNAR INDEX FROM xxx_db.xxx_tb; # Query the CCIs of the xxx_tb table on the xxx_db database (for across-database query)You can also execute the SHOW INDEX statement to view index information. For more information, see SHOW INDEX.
Examples
SHOW COLUMNAR INDEX;
+---------------+---------+-------------------+-----------+-----------+----------------+---------------+--------------------+-----------------+-----------+--------+
| SCHEMA | TABLE | INDEX_NAME | CLUSTERED | PK_NAMES | COVERING_NAMES | PARTITION_KEY | PARTITION_STRATEGY | PARTITION_COUNT | SORT_KEY | STATUS |
+---------------+---------+-------------------+-----------+-----------+----------------+---------------+--------------------+-----------------+-----------+--------+
| columnar_test | t_order | cc_i_seller_$07f0 | true | id | | order_id | DIRECT_HASH | 16 | seller_id | PUBLIC |
+---------------+---------+-------------------+-----------+-----------+----------------+---------------+--------------------+-----------------+-----------+--------+The following table describes the parameters in returned results.
Parameter | Description |
SCHEMA | The name of the database. |
TABLE | The name of the table. |
INDEX_NAME | The name of the index. |
CLUSTERED | Specifies whether the index is a covered index. Valid value: true. |
PK_NAMES | The primary key column. |
COVERING_NAMES | The covering column. |
PARTITION_STRATEGY | The partitioning type. |
PARTITION_COUNT | The number of partitions. |
SORT_KEY | The sort key |
STATUS | The status of the index. Valid values:
|