SQL Server 2012 SSIS查找缓存不起作用

Question

I'm using SQL Server Data Tools in Microsoft SQL Server 2012 to load data from the staging to the data warehouse. During the ETL process, I use the Lookup Transformation to get the dimension key from the lookup table into my fact table. My issue is that when I use the Full Cache in Lookup Transformation, all the rows went to the no match output. When I use Partial cache or No cache, all the rows went to the match output as is supposed to be. I'm really confused and don't understand what's going on here. I really need some help here.

Thanks, Dan

Answer 1

If you are looking up based on a VARCHAR or NVARCHAR field, as billinkc has suggested, if the fields are in different cases (Dan Vs dan) this would lead to a no match. Try doing an derived column of UPPER(SourceColumn) and use the query in the lookup Transformation to Select UPPER(MatchingColumn), LookedupKey from LookupTable and match on this.