Reviewed-by: Hasko, Vladimir <vladimir.hasko@t-systems.com> Co-authored-by: Yang, Tong <yangtong2@huawei.com> Co-committed-by: Yang, Tong <yangtong2@huawei.com>
7.8 KiB
CREATE SECONDARY INDEX
Function
This command is used to create secondary indexes in the CarbonData tables.
Syntax
CREATE INDEX index_name
ON TABLE [db_name.]table_name (col_name1, col_name2)
AS 'carbondata'
PROPERTIES ('table_blocksize'='256');
Parameter Description
Parameter |
Description |
---|---|
index_name |
Index table name. It consists of letters, digits, and special characters (_). |
db_name |
Database name. It consists of letters, digits, and special characters (_). |
table_name |
Name of the database table. It consists of letters, digits, and special characters (_). |
col_name |
Name of a column in a table. Multiple columns are supported. It consists of letters, digits, and special characters (_). |
table_blocksize |
Block size of a data file. For details, see •Block Size. |
Precautions
db_name is optional.
Examples
- CREATE INDEX productNameIndexTable on table productdb.productSalesTable (productName,city) as 'carbondata';
In this example, a secondary table named productdb.productNameIndexTable is created and index information of the provided column is loaded.
- CREATE INDEX t1_index1 on table t1 (c7_Datatype_Desc) AS 'carbondata' PROPERTIES('table_blocksize'='256');
System Response
A secondary index table will be created. Index information related to the provided column will be loaded into the secondary index table. The success message will be recorded in system logs.