Help Center> MapReduce Service> Component Operation Guide> Using CarbonData (for MRS 3.x or Later)> CarbonData Syntax Reference> DDL> REFRESH INDEX
View PDF

REFRESH INDEX

Function

This command is used to merge all segments for data files in the secondary index table.

Syntax

  • REFRESH INDEX indextable_name ON TABLE maintable_name

    This command is used to merge all segments for which data files are to be merged.

  • REFRESH INDEX indextable_name ON TABLE maintable_name WHERE SEGMENT.ID IN (0,1,2..N)

    This command is used to merge a batch of specified segments.

Parameter Description

Table 1 REFRESH INDEX parameters

Parameter

Description

indextable_name

Name of an index table

maintable_name

Name of the primary table

Precautions

To clear the data file of compacted segments, run the CLEAN FILES command on the secondary index table.

Examples

REFRESH INDEX productNameIndexTable;

System Response

After this command is executed, the number of data files in the secondary index table will be reduced.

Parent topic: DDL