DataColumn Expression Aggregate Function with Filtering RRS feed

  • Question


    I have a DataSet with two DataTables.  The second DataTable is a child of the first parent DataTable via a DataRelation.  I want to have a DataColumn in the parent DataTable that uses an aggregation function like Count, but I only want to count rows in the child table that meet a certain filtering criteria.  An example of what I want is something like:


    Count(Child([ChildTable]).[ColumnToTest] = 'Value To Test For')


    When this expression is evaluated I get the following error message:


    "Syntax error in aggregate argument: Expecting a single column argument with possible 'Child' qualifier."


    In a Sql Query I would use something like:


    SELECT Count(*) AS MyResult FROM ChildTable WHERE ColumnToTest LIKE '%Value To Test For%' GROUP BY ParentID


    Does anyone have any suggestions about how to do what I want do?


    Thanks in advance.

    Sunday, November 16, 2008 3:01 PM