Understanding LinkType in Form Data Sources in D365 F&O

In Dynamics 365 Finance and Operations, the `LinkType` property connects data sources (tables) in a form and controls how they work together. Here's a simpler explanation:

1. Active (default):

- The child data source (table) automatically updates when you select a record in the parent data source.

- Example: If you pick a sales order in SalesTable, it automatically shows matching lines in SalesLine.

2. Delayed:

- The child data source does not update immediately when the parent changes.

- Example: The child only refreshes when you manually request it (e.g., press a button).

3. Passive:

- No automatic filtering or updating happens.

- Example: You control everything manually through custom code.

4. InnerJoin:

- Only shows records that match between parent and child.

- Example: If no sales lines exist for a sales order, that order won't appear.

5. OuterJoin:

- Shows all records from the parent and any matching records from the child.

- Example: All sales orders are shown, even if they don't have lines.

6. ExistJoin:

- Shows parent records that have at least one matching record in the child.

- Example: Sales orders that have at least one sales line.

7. NotExistJoin:

- Shows parent records that do not have matching records in the child.

- Example: Sales orders with no sales lines.

You set `LinkType` in the form data source properties in Visual Studio. It helps the system decide how data flows between related tables in your form.