Data Integrity and Storage
provides a number of capabilities to check on the quality of data on a node and to quarantine segment groups that are problematic for any reason. Also related to data integrity is the ability to Rebuild Tasks and Check Data.
ALTER SEGMENT QUARANTINE isolates segment groups from segment generation or queries. Use this SQL statement if segments are causing unexpected results or crashes. The segments can be un-quarantined by setting quarantine_level to none.
The identification numbers for segment groups.
Depending on your ALTER SEGMENT QUARANTINE statement, the Ocient system quarantines the specified segment groups for having an existing quarantine removed.
For more information on finding abnormal segments, see the Guide to Rebuilding Segments.
You can place quarantines at the following segment levels:
Isolates the specified segments from segment generation.
This statement prevents corrupt data from causing problems while still leaving the data available for future analysis.
Isolates segment groups from subsequent queries.
Data that is quarantined at the query level is not returned by database queries. This can be useful to prevent corrupt data from causing query problems while still leaving it available for future analysis.
Isolates the specified segments from segment generation and subsequent queries.
Removes any quarantines from the specified segments.
This example quarantines a single segment group from segment_generation.
This example quarantines multiple segment groups from segment_generation.
This example removes a quarantine from a single segment group.
This example removes a quarantine from multiple segment groups.
This example quarantines at the query level.
This example removes a quarantine at the query level.
This example quarantines at both the query and segment-group levels.