Deletion in Vertica

• https://my.vertica.com/docs/6.0.x/HTML/index.htm#15116.htm

DELETE_VECTORS

Holds information on deleted rows to speed up the delete process.

Column Name	Data Type	Description
NODE_NAME	VARCHAR	The name of the node storing the deleted rows.
SCHEMA_NAME	VARCHAR	The name of the schema where the deleted rows are located.
PROJECTION_NAME	VARCHAR	The name of the projection where the deleted rows are located.
STORAGE_TYPE	VARCHAR	The type of storage containing the delete vector (WOS or ROS).
DV_OID	INTEGER	The unique numeric ID (OID) that identifies this delete vector.
STORAGE_OID	INTEGER	The unique numeric ID (OID) that identifies the storage container that holds the delete vector.
DELETED_ROW_COUNT	INTEGER	The number of rows deleted.
USED_BYTES	INTEGER	The number of bytes used to store the deletion.
START_EPOCH	INTEGER	The start epoch of the data in the delete vector.
END_EPOCH	INTEGER	The end epoch of the data in the delete vector.

• https://my.vertica.com/docs/6.0.x/HTML/index.htm#9931.htm

PURGE

Purges all projections in the physical schema. Permanently removes deleted data from physical storage so that the disk space can be reused. You can purge historical data up to and including the epoch in which the Ancient History Mark is contained.

Syntax

PURGE()

Privileges

• Table owner
• USAGE privilege on schema

Note

• PURGE() was formerly named PURGE_ALL_PROJECTIONS. HP Vertica supports both function calls.

Caution: PURGE could temporarily take up significant disk space while the data is being purged.

See Also

MERGE_PARTITIONS

PARTITION_TABLE

PURGE_PROJECTION

PURGE_TABLE

STORAGE_CONTAINERS

Purging Deleted Data in the Administrator's Guide