NBACKUP incremental restore improvment

[Hugolarson]

The FB4 GUID based nbackup and incremental restore are huge improvement and we would like to use it as an convent way for replica solution and also use the replica db to generate reports.

We found out that no user can be connected to the replica db when doing a incremental restore. During backup a delta file is created and it's then merged when nbackup is finished. Why can't the incremental restore be the same and allow connection and allow read only queries?

[hvlad]

Incremental restore could merge increment into database in the similar way as delta file merges. The file format of increment and delta is different but it is not a main problem. The real problem is metadata changes contained in increment. It should be detected somehow and corresponding part of metadata cache and prepared user statements should be invalidated.

[Hugolarson]

"The real problem is metadata changes contained in increment." Do you mean when structure of the DB changes? Like Tables, Triggers etc?

How about having two inplace restore: "Heavy" -> Like now. No connections allowed. "Light" -> Only data is changed. Allow connections.

[Hugolarson]

Hi, Just checking here after a couple of months with hope of a way to incremental restore nbackup without having to disconnect all users. Thanks,