SSRS 表达式问题。 无法在表达式中使用嵌套聚合

Question

I'm trying to write an expression in SSRS where i am trying to use field from another dataset in SUM function but I keep getting the error message below:

The Value expression for the textrun 'Textbox41.Paragraphs[0].TextRuns[0]' uses a First, Last or Previous aggregate in an outer aggregate. These aggregate functions cannot be specified as nested aggregates.

This is how my expression looks:

=TimeSpan.FromTicks(Sum(TimeZoneInfo.ConvertTimeFromUtc(Fields!Diffrence.Value,TimeZoneInfo.FindSystemTimeZoneById(First(Fields!TimeZoneIDForCS.Value, "DS_Master")))))

Answer 1

Without knowing what your dataset looks like or the scope of the expression (where it sits in your report) it's hard to give a definitive answer but try these suggestions.

If the value of TimeZoneIDForCS is the same, use MAX() instead of FIRST().

Move the scope reference from the FIRST() function to the SUM() function.