Release 10.1A: OpenEdge Development:
ProDataSets

Using the AUTO-SYNCHRONIZE attribute

As we have discussed, Progress doesn’t automatically synchronize all relation queries whenever any of them are positioned to a different row, because the expense of this could be considerable in some cases, and might not always be wanted. When a browse widget is initially filling the viewport, for example, it repositions its underlying query as it transfers values for each row to the browse, until the viewport is filled. It makes no sense to refilter and reopen child relation queries for each momentarily selected parent row. Beyond this, these relation queries are provided for convenience only, and many application situations might not make use of them at all.

However, in situations where the parent table of a Data-Relation is not viewed in a Progress browse control, and where the application is making use of the relation queries, it can simplify the programming not to have to insert SYNCHRONIZE methods in all the places where the current row position might be changed. To support this, there is an AUTO-SYNCHRONIZE Logical attribute available for both the ProDataSet and each ProDataSet temp-table buffer. This is initially FALSE and is never set to TRUE by Progress. If it is set to TRUE by the application, then every change of row position in an affected ProDataSet buffer causes a SYNCHRONIZE automatically, just as invoking the SYNCHRONIZE method would do. Setting the attribute to TRUE for the ProDataSet effectively sets it to TRUE for all its buffers. Otherwise, you can selectively set it for individual buffers where you want the automated synchronize behavior.