DROP SEGMENT_SET

Delete the data node collection.

Summary

DROP SEGMENT_SET name;

describe

A data node set (Segment Set) refers to a specific set of data nodes in a cluster. After defining a specific data node collection, in the database definition language (DDL) statement that is being built or modified, the created data node collection can be specified so that the data of the table is only distributed on these data nodes, otherwise it will be distributed in all nodes in the cluster by default.

A data node collection is a logical concept that does not actually contain any actual data on any data nodes, and deleting a data node collection will not remove the corresponding node from the cluster. Similarly, creating and deleting data node collections will not affect the actual expansion and shrinking of the cluster, nor will the table data be changed.

Two different sets of data nodes may contain one or more data nodes of the same.

The DROP SEGMENT_SET command deletes a created collection of data nodes at the database level.

Parameters

NAME

  • The name of the data node collection, there is a special reserved data node collection name ALL_SEGMENTS cannot be used, it represents all data nodes under the current cluster size. As the cluster expands, the list of data nodes pointed to by ALL_SEGMENTS will be different.

Example

Delete the created data node collection ss1.

DROP SEGMENT_SET ss1;

Notes!
There is no dependency between the data node collection and the table. After deleting the data node collection specified in the table, the table can still be operated normally.

compatibility

DROP SEGMENT_SET is a YMatrix database extension, and there is no concept of node collection in the SQL standard.

See also

CREATE SEGMENT_SET, ALTER TABLE