How do I know the sequence of execution of CIG mappings?

CIG will execute the mappings in the following order:

1. First, CIG executes the standard out of the box mappings.
2. Next, CIG executes the customized backend manual XSLT mappings done by engineering if any ( You would have raised an Ariba Case during your implementation phase requesting engineering to perform these custom backend XSLT mappings on behalf of you that cannot be fulfilled by CIG Mapping Tool). 
3. Last, CIG executes the custom mappings done via CIG Mapping Tool.

If you map the same fields via CIG Mapping Tool as Engineering had mapped via backend custom XSLT mapping, CIG will overwrite the Engineering custom mapping behavior with the behavior set in the CIG Mapping Tool.

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