Cascading multi-value parameter issue in SSRS 2008 <p>Basically I have built a report using SSRS 2008, the report has cascading parameters, the independent one is a multi-value parameter (work units) populated with values from a database query, the dependent parameter (job positions contained in respective work units) also gets values from a query with a where clause as follows:</p> <pre><code>WHERE position.unitId IN (@units) </code></pre> <p>@units being the multi-value parameter. The default value for units is the query itself - all of which the user has access to. So upon opening the report, all available units are selected and all respective job positions are retrieved - works fine. But a aser can also have no access to any units, which makes the dependent query fail, cause no units were retrieved hence @units contains no values. I would have thought the query would not fire until @units has a value present.. anyways I have tried to check the contents of @units before querying for job positions in various ways:</p> <p>*replacing @units parameter with the following expression: =IIF(Parameters!units.Count = 0, "00000000-0000-0000-0000-000000000000", Parameters!units.Value)</p> <p>*having another parameter containing a comma seperated string of the @units values and checking if the lenght of that is greater than 0 before executing the dependent dataset, etc.</p> <p>But now, when I open up the report, the drop down list of job position is empty, disabled and remains so until the values of units are changed or the report is run. After that they refresh alright it seems. So my question is, what may be the cause of the control being disabled (units are retrieved, so why does an expression as a parameter value for job positions messes it up?) and how to deal with this the right way, can`t seem to find something really of the same nature online. </p> <p>Any help will be greatly appreciated.</p>