Passing Multi-value Parameters to a MDX Query in SSRS

Let’s say our report needed ProductCategory as a parameter.  The ProductCategoryKey in the relational database for Bikes is 1, and our cube member for Bikes is [Product].[Category].&[1].  So we can transform our parameter value to pass into our mdx query like so:

“[Product].[Category].&[”+Cstr(Parameters!ProductCategory.Value) + “]”

Simple right?

BUT, I needed to be able to pass multiple values, which meant I had to take some extra steps before I could parse my string.  If ProductCategory is a multi-value parameter, then Parameters!ProductCategory.Value is an object – an array of values.  So we need to create a single string out of that array, format that string, and then break it up again back into an array since that is what the MDX query is expecting.  Whew!

Here’s the magic:

Split(“[Product].[Category].&["+Replace(Join(Parameters!ProductCategory.Value,"],”)+”]”,”,”,”,[Product].[Category].&["),",")

Cool eh? but, what’s happening here?

Join() is a handy little function that takes our array and joins the values into a string.  We can delimit the values with a string, in this case “],”, like so:

Join(Parameters!ProductCategory.Value, “],”)

Bikes, Components, and Clothing for our parameter values, our string after using the join function will be“1],2],3″.  We can then add an ending bracket to the end via simple string concatenation so now we have “1],2],3]”.

Applying the Replace() function, we replace “,” with “,[Product].[Category].&[“ and now we have “1],[Product].[Category].&[2],[Product].[Category].&[3]“.  Finish with one final string concatenation in the front and we have “[Product].[Category].&1],[Product].[Category].&[2],[Product].[Category].&[3]“

Unfortunately we can’t just pass this into our MDX query.  It’s expecting an array object, not a string!  But luckily, the Split() function is the counterpart to Join() and breaks up our string into that array object we want via the commas as a delimiter.