Parent and child data source is updated immediately when a new record in the parent data source is selected. Continuous updates consume lots of resources consuming.
Parent and child A pause is inserted before linked child data sources are updated. This enables faster navigation in the parent data source because the records from child data sources are not updated immediately.
For example, you can scroll a list of orders where you do not want to review the lines associated with the order until you stop scrolling.
Parent and child Linked child data sources are not updated automatically. Updates of the child data source must be programmed on the
active() method of the master data source.
Combined data source select the record from the main table that matches records in the joined table and vice versa.
There is one record for each match. Records without related records in the other data source are eliminated from the result.
Combined data source select the records from the main table. The records are retrieved whether they have matching records in the joined table
Combined data sourceThe data source retrieves a record from the main table for each matching record in the joined table.
The differences between InnerJoin and ExistJoin are as follows:
When the join type is ExistJoin, the search ends after the first match has been found.
When the join type is InnerJoin, all matching records are searched for.
Combined data sourceSelect records from the main table that do not have a match in the joined table.