Mapping Items

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Mapping Items

Normally, corresponding items are mapped automatically in DatabaseSpy, however if, for example, different naming conventions are applied on the compared databases, automatic mapping might fail. In this case, you can still map corresponding items manually, by drawing a line between the respective items.

 

If you check the sorted tables in your database schema comparison, you will notice that item dbo.tblVeterinarians is not mapped to test.tblVets. Obviously, the difference in the name of the two items was too big for the automatic mapping to identify these two items as a comparison pair.

diffs_mapping-sorted

We will now take a closer look on these two items to determine whether or not they can be considered corresponding. Double-click the items or click the plus sign to expand the table in the comparison components. Since the columns that are contained in the table are pretty similar in the left and right components, we can map them and hence include them in the comparison. Note that all child items of the tables that are equal on both sides will be mapped automatically when you draw the connection line between the parent.

diffs_vets-expanded

Two column pairs, LastName/Name and Telephone/Phone, are still unmapped, if you further expand these items, you will see that data types as well as Nullable constraints are equal on both sides and that these items can also be mapped safely.

diffs_details-expanded

 

To manually map dbo.tblVeterinarians and test.tblVets:

1.In the Schema Comparison window, click the triangle next to dbo.tblVeterinarians and, keeping the mouse button pressed, draw a line to test.tblVets. Release the mouse button when the cursor changes its shape.

diffs_mapping-table

2.Double-click either dbo.tblVeterinarians or test.tblVets to expand the table in both components and map column "LastName" to column "Name" as described in step 1.

diffs_mapping-column

3.In the same way, map column "Telephone" to column "Phone".

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