On the other day I came across a interesting functionality in the SSRS. They are Lookup and Lookup set functions , these functions are very useful for multi source reports
Simple Abstract :
Lookup : Just like the Excel Vlookup function which can get the data from another dataset
Lookupset: Same like lookup but returns all the matching results and will be very useful for displaying all the matching results, This can be converted to comma separated form using Join function.
Check the Below Blog for details
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