Interceptors capabilities to change rows

[jromerus]

Hi, regarding to interceptors I'm reading this:

Or even intercept all the rows that are going to be applied on a destination database

I wonder if I could remove columns from specific rows. My aim is avoid syncing all the fields of a row, if possible. My software can track field changes and saves information of last field date time change from each row of tracked entities. With an intercerptor I could get which fields from that row need to be synced. So the question is, could I remove not changed columns and sync to the client (or to the server) only desired ones?

[Mimetis]

I don't think so, because DMS uses the order of the columns and the index to generate the statements.
That means if you don't have the same columns count / order than what is specified in the SyncSetup, it will fail.
That being said, I've never tested it...

Maybe, you can try different interceptors I guess, the nearest interceptors from the insert / update / delete command are, in order : OnGetCommand , OnRowsChangesApplying then OnExecuteCommand.

[jromerus]

Ok, I thought column name was included in the data sended or received. Do you think I could add that information into the "row package", in order to send only desired columns with names (changed columns) and process them overriding standard behaviour? I suppose I would need to override serialization, deserialization and database command building based on new deseraization that would include column name.

Instead of using my tracking column changes maybe I could use a a more "universal" approach with interceptores saving a "snap shot" of each processed row into some kind of cache (with string to hash to reduce size) , and analyze row differences (actual row against previous one).

[Mimetis]

Yes, including column names is a feature I wanted to integrate, but I need to stay compatible with the previous versions as much as I possibly can.
Maybe in a future version, I guess.

Before sending the generated batch files, using OnTableChangesSelected or even OnDatabaseChangesSelected, you still open these batch files and add your custom json

Or, you can use the property AdditionalProperties from your SyncContext instance, to add anything you want, and use it on purpose on the other side.

Once again, hard to help you here, without a simple example to reproduce.