When using the PipelineToolkit.IdentifierMappers plugin, an attempt to re-configure an Identifier Mapper results in an error. 

Please recheck these fields: 0: SQLSTATE[42702]: Ambiguous column: 7 ERROR: column reference "id" is ambiguous LINE 1

To recreate this:

1. create or edit a Pipeline (if create, save it)
2. click "Flanges" (upper right link) 
3. click "Add a New Flange" (upper right link)
4. Set the Flange plugin to PipelineToolkit.IdentifierMappers and save it
5. Under plugin configuration, select "Login Identifier Types" (upper right)
6. Select "Add a New Login Identifier Type" (upper right)
7. Set the type to any identifier type (e.g. "Enterprise") and save it.
8. Revisit the Login Identifier Type you've just created, change the identifier type, and save it. 

This will show the error similar to this screenshot: