Data Retention

Data retention policy can be realised by TStorage using special USConnector command - DELETE. It deletes data by key ranges (keyMin, keyMax). DELETE removes whole partitions - key range is rounded to partitions boundaries.

Description

Only whole partitions are deleted. i.e., those fully covered by the DELETE key range. If the key range does not cover the whole key range that logically belongs to a given partition, the partition is not deleted. PUTs are not allowed within key range, for which deletion is pending. Otherwise, interleaved PUTs and DELETEs may corrupt range partition.

Usage

1. Client that executes deletion can connect only to a USConnector which resides on the same machine as Client.

2. Unblock deletion (reference to commandserver.py usage) on the USConnector.

3. Perfrom DELETE request on the USConnector.

4. Block deletion on the USConnector.

DELETE Command

To use this command, one has to enable it on the USConnector first.

DELETE Request

cmd = 4

size = size of KeyRange

DELETE Response - SUCCESS

result = 0

size = size of KeyRange

USConnector sends back key range that was taken into account while deleting.

DELETE Response - ERROR

result = 1

size = 0