Update single column in a table (Update single field in cdt)

Query Database Approach will be good, but Appian does not suggest that because its not a best practice.
If you configure Query database, after deployment to other environments then you to open the model and reconfigure it again (if data source changes).

You can create a datatype to update that particular field, but if you want to update column 1 in one model and column 2 in 2nd model and so on.
Then you cannot create so many data types for required columns to update.

My suggestion is that use Write to data store entity smart service and pass full CDT.
Because this will not result into any performance issue not manual update when data source changes.

Query Database Approach will be good, but Appian does not suggest that because its not a best practice.
If you configure Query database, after deployment to other environments then you to open the model and reconfigure it again (if data source changes).

You can create a datatype to update that particular field, but if you want to update column 1 in one model and column 2 in 2nd model and so on.
Then you cannot create so many data types for required columns to update.

My suggestion is that use Write to data store entity smart service and pass full CDT.
Because this will not result into any performance issue not manual update when data source changes.