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.