Build dynamic query(dynamic operator) in SSRS using a complex query

I would like to build a dynamic query for a specific report using some parameters (dynamic operators).

How can I add dynamic parameters without writing/editing the expression?

Because my query is complex, included three-join tables and aggregations I think this might be cause the error.

Can I join tables within an expression in dataset properties?

SELECT  a.CaseNo, a.PatientName, a.PolicyNumber,

FROM Cases a

INNER JOIN GOPs b ON a.CaseNo = b.CaseNo

INNER JOIN Invoices d ON d.CaseNo = a.CaseNo 

WHERE (a.CreatedDate >= @StartDate AND a.CreatedDate <= @EndDate +1)

This query is working properly if I write it directly in query editor. However, when I put it as an expression does not work anymore.

Also, I would like to add dynamic operators to that query. The only solution is to put it as an expression. E.g. at the end of the query I want to add the following:

AND FeeEuro "+ Parameters!Operator.Value + Parameters!OperatorValue.Value

something like that

AND FeeEuro > 200

Is it possible to do what I need to do, if so can you point me in the right direction?

There are a few approaches here.

I created some sample data to test against:

create table ReportTest
(id int, value int, testDate date)

insert into ReportTest
values
(1, 100, '01-jan-2013'),
(2, 200, '01-feb-2013'),
(3, 300, '01-mar-2013'),
(4, 400, '01-apr-2013')

I've also added three parameters:

Date
Operator (available values are < and > for my report)
OperatorValue (integer)

Expression-based

First question is why did your query work in the editor but not as an expression?

You can reference parameters in the editor and SSRS will transform these as required, if possible. This works fine for the date parameters as you've seen, but SSRS won't know what to do with the Operator parameter.

When using an expression-based DataSet, SSRS will apply no transformation at all - it will just try and put a string together then throw this at the Data Source and hope it works. This means that the expression has to apply any formatting/updating itself to create an appropriate query.

The following worked for me with the above table/parameters:

="select * from ReportTest where testDate > '"
  & CDate(Parameters!Date.Value).ToString()
  & "'"
  & " and value " & Parameters!Operator.Value & " " & CStr(Parameters!OperatorValue.Value)

So when applied this is turned into a usable query that works as required.

You do get a warning when applying this:

This makes sense as SSRS can't tell what will be received before actually running the dynamic query.

As such you'll need to set up the columns before moving to an expression-based query.

Editor-based

It's difficult to apply an operator-type parameter without dynamic SQL, but you can do something similar with a CASE statement. This works for me through the query editor:

select *
from ReportTest
where testDate > @Date
  and ((@Operator = '>' and value > @OperatorValue)
    or (@Operator = '<' and value < @OperatorValue))

Depending on how you look at it, the query is slightly more complex, but it does avoid having to use an expression-based query.

Both of the above examples worked on my simple table: