Data Mapping

Table Mapping

Once the target system has been identified and fully documented, we develop a series of detailed data maps based on the legacy and target system “rules” describing how data is to migrate from legacy element ‘x’ to target element ‘y’.  Before mapping at the element level however, table mapping must occur to describe what constitutes a record being created in a target table.  Which legacy table(s) are involved in creating this record and how do those legacy tables tie together.  An example of table mapping is shown below:



Element Mapping

Once the table mapping is defined, element-level mapping is then added to define which element(s) in the legacy system(s) will make up the element in the target system.  Many conditions could factor into how to derive the target element.  For example, when a specific code is set to ‘x’, one field may be used to populate the target element, but when the code is set to ‘y’, another field is used.  Some element-level mapping will be 1-to-1 mapping meaning one source element converts to one target element, but many times, its more complex than that.  The CMT handles all the element level mapping including code to code mapping as well.  A sample element-level mapping page is shown below: