The DROP SYNC BOOKMARK statement drops a bookmark defined on a master database. Bookmarks are typically used when exporting data to a file. After a file is successfully imported to a replica from the master database, it is recommended that you drop the bookmark that you used to export the data to a file.
To drop a bookmark, you must have administrative privileges (SYS_ADMIN_ROLE or SYS_SYNC_ADMIN_ROLE). The DROP SYNC BOOKMARK statement cannot be used in a replica database.
If a bookmark remains, all subsequent changes to data on the master including deletes and updates are tracked on the master database for each bookmark to facilitate incremental refreshes.
If you do not drop bookmarks, the history information takes up disk space and unwanted disk I/O is incurred for each bookmark registered in the master database. This may result in performance degradation.
Note Bookmarks should only be dropped after the exported data is imported into all intended replicas and after all the replicas have synchronized at least once. You should drop a bookmark only when you no longer have replicas to import and those replicas have refreshed once from the publication after the import.
When dropping bookmarks, solidDB® uses the following rules to delete history records:
▪Find the oldest REFRESH delivered to any replica on that table.
▪Find the oldest bookmark.
▪Determine which is older, the oldest REFRESH or the oldest bookmark.
▪Delete all rows from history up to what is older, the oldest REFRESH or oldest bookmark.