Column mapping involves the proper mapping of Source to Target Columns. In some cases where Transforms have been designed using Free-Form SQL, or designed in the Query Builder, the defaults that have been provided might enable the user to simply hit the NEXT button, which will move them to the Index Mapper screen.
However, the following scenarios will involve using the GUI controls to select the proper Column Mapping.
| New Derived Column | New Columns can be added when the Designer has selected Single
Table Transform. The Designer will select
the "Add Row" button. This will produce an empty row in which the user can create a Derived field using SQL Language. An example could be: Order Quantity +1 as Undercapitalized |
Single Table Transforms |
| Deleting a Column | If Single Table Transform is selected, there might be situations where certain columns aren't needed in the target table. The designer can highlight the specific row, and choose to delete it. The "Delete Row" button will be pressed. | Single Table Transforms |
| Moving Row up and down | This has the net effect of moving the specified column so that it appears in a different location with respect to the Created table. For instance if order id was listed as the first column, but the designer wanted it as the third column, the designer could press the Row Up/Row Down button to change its location. | Single Table Transforms
Query Builder Transforms Free-Form SQL Transforms |
| Adjustments to Target Table Attributes | Target Table names, datatypes, lengths, precisions, and scales can be changed. Generally, this should be done with caution, as the default values might be appropriate. | Single Table Transforms
Query Builder Transforms Free-Form SQL Transforms |
Examples:
Adding a Derived Column
After Add Row was selected, the designer needs to enter the fields above that are circled. In the case of Data Type, a drop-down list is provided. In the case of the Column Names, The user should type the appropriate Target Column Name, and SQL Transformation.
Delete Row
In this scenario, the highlighted row will be deleted. It is important to avoid deleting columns that might be a unique key, as Incremental synchronization depends on having a unique key.
After the designer is done with column mapping, the last part of the Transformation tasks deals with Index Mapping.