Manual mapping

In a previous post I’ve warned about the not so automatically behavior of the automatic mapping. However, I can’t blame the manual mapping for the same degree of inconsistency. I mean, boy, that’s as manual as it gets!

Take a manually mapped attribute and have a look at its source tables. Now drop the attribute from one of these tables (on database and Catalog level) and try to run a report which used that table.

On the one hand, MSTR knows from the attribute definition that it can include that table into the SQL. On the other hand, it should know from the table definition, as updated in the Warehouse Catalog, that the column is no longer there, but such a small detail doesn’t have enough force to deter the SQL Engine. So it simply writes the SQL as if nothing had happened, and the only error you get is from the database (i.e. a11.attribute_id does not exist).

So, if you aren’t doing this already, don’t forget to inform the manually mapped attribute that one of its source tables decided to discontinue their relationship, next time you indulge in such data model changes.