How to substitute NULL parameter for subreport? - reporting-services

I am using SSRS 2008 R2. My RDL has several subreports in it which all take one field value only from this parent RDL as their inputs. This one field value is called "people_id". There are some instances though where there are 0 records returned from the parent RDL. When this happens, I get the following error when I run this report from the parent RDL:
An error occurred during local report processing. Object reference not set to an instance of an object.
Even though I tried setting the paremeter value for my subreports to both:
people_id
and
=iif(isnothing(Fields!people_id.Value),"",Fields!people_id.Value)
How can I successfully avoid this error when there are no records?

I guess it's too late but in case of helping anyone else.
Some values in an expression can evaluate to null or undefined at report processing time. This can create run-time errors that result in #Error displaying in the text box instead of the evaluated expression. The IIF function is particularly sensitive to this behavior because, unlike an If-Then-Else statement, each part of the IIF statement is evaluated (including function calls) before being passed to the routine that tests for true or false. The statement =IIF(Fields!Sales.Value is NOTHING, 0, Fields!Sales.Value) generates #Error in the rendered report if Fields!Sales.Value is NOTHING.
From http://msdn.microsoft.com/en-us/library/ms157328.aspx
I had a similar issue and ened up with writing a custom function.

Instead of =iif(isnothing(Fields!people_id.Value),"",Fields!people_id.Value), can you try =iif(isnothing(Fields!people_id.Value),NOTHING,Fields!people_id.Value)?

Related

Error when trying to use Where clause in SSRS expression

This SO link, WHERE Caluse in SSRS expression, verifies that my syntax is correct yet I get this error:
"An error occurred during local report processing.
The definition of the report is invalid.
The Value expression for the text box 'txt1A_EMA' uses an aggregate expression without a scope. A scope is required for all aggregates used outside of a data region unless the report contains exactly one dataset."
My expression:
=Sum(IIF((Fields!COU_EMA.Value, "CA_Summary") = 1, (Fields!Amount.Value, "CA_Summary"), 0))
There are 3 Datasets in my report. The one I want is "CA_Summary" and the expression above was built with the expression builder.
The field, (Fields!COU_EMA.Value, "CA_Summary"), is a boolean (1 or 0) and I get error either with a 1 or a "true" (no quotes).
I probably could fix it if I knew what the definition of "scope" is. . . maybe.
The scope is where you want to look in order to get the values you're looking for. It could be a data set, group, etc. In your expression it appears CA_Summary is the scope.
I would try modifying the expression a bit. Since you say COU_EMA is bit field, maybe use TRUE. This is also assuming the matrix is using the data set CA_Summary.
=Sum(IIF(Fields!COU_EMA.Value = TRUE, Fields!Amount.Value, 0))
If your matrix isn't using that data set and it still doesn't work try
=Sum(IIF(Fields!COU_EMA.Value = TRUE, Fields!Amount.Value, 0),"CA_Summary")

using RenderFormat.IsInteractive in SSRS query

I am creating a SSRS report where I require to call different queries based on some condition. mainly with Globals!RenderFormat.IsInteractive.
If Globals!RenderFormat.IsInteractive is true call 1st query block otherwise other query block.
In query itself it is not possible to create IF condition using Globals!RenderFormat.IsInteractive. so I tried creating report variable and parameter with default value of Globals!RenderFormat.IsInteractive but both giving error of query refers to the global variable RenderFormat, which is not valid for this type of report item expression.
Is there any workaround for it?

Adding Fields into an expression in an SSRS 2008 report

Thank you in advance for taking your time to answer my question.
I am having trouble with expressions in the SSRS reporting system.
The Field I am adding required fields from the dataset I provided in the report, however when I try to preview the report I get the Following message:
"A Value expression used for the report parameter ‘Policies_Total’
refers to a field. Fields cannot be used in report parameter
expressions."
This is my expression:
=IIF(Sum(Fields!policy_id.Value, "DataSet1") Is Null, 0, Count(Sum(Fields!policy_id.Value, "DataSet1")))
That was suppoed to be converted from Crystal reports which has the following expression:
If IsNull ({usp_rep_agent_cases;1.policy_id}) then
0
Else
Count ({usp_rep_agent_cases;1.policy_id})
Any help is much appreciated.
Thank you
I think it may be as simple as understand that a 'parameter' should be passed into SSRS before fields are created for the most part. If this parameter is DEPENDENT on the value of something else first being chosen you cannot list it first as the field is not yet populated to my knowledge. It appears you are trying to use an expression to count something from a field from a dataset when you just make a dataset and reference that field directly. So instead of trying an expression you may choose a few other options instead:
Choose on the left pane of your parameter 'Available Values' selected 'Get values from a query'. You may use your query which is a 'dataset', value is self explanatory, label is what the end user will see display.
The option 'Allow null' value will accept a null value
You may run into situations where multiple datasets may need to be used, multiple selects or querying objects. In my experience with SSRS it gets mad at times when you try to reference a dataset used to display data with a dataset used to determine an event or action. SSRS also gets relativity slower the more Expressions you do so doing a whole report with nothing but expressions versus taking the power of the built ins of the RDL language is not really worth it IMHO.
For SSRS expressions you need to use IsNothing for NULL checking, something like:
=IIF(
IsNothing(Sum(Fields!policy_id.Value, "DataSet1"))
, 0
, Count(Sum(Fields!policy_id.Value, "DataSet1"))
)
In fact the whole expression seems a bit odd; what are you specifically trying to achieve with your expression? Are you just trying to count non-null values?
=Sum(IIf(IsNothing(Fields!policy_id.Value), 1, 0), "DataSet1")
Also, your error seems to be saying that a parameter is referencing a field when this isn't allowed, which may not be solved by changing syntax; I think more information about what you're trying to achieve is required here.

Reporting Services problem. Forward dependencies are not valid

I have a problem with a Reporting Services report. My report has two datasets, one that fetches the actual report data and one that fetches translated resource strings for displaying wherever literal text is used on the report. This dataset requires three parameters, a language set id, a language code and a string to match against resource names.
Following an example I found here (the reply by Miguel Catalão) I have created a multivalue parameter #Resources that will be populated from the resource dataset and a code function that looks up specific values from the multivalue query. This function will then be called from expressions wherever literal strings are used.
I think that this should work but I have run into a problem that I can't quite figure out a workaround for. There is a dependency problem in the #Resources parameter being dependent on the Resources dataset which in turn is dependent on three parameters; #LanguageSetID, #LanguageCode and #ResourceNameLookup. I have read that the order of declaring parameters is important so I have made sure that the last three parameters appear above the #Resources one and that all three of them have default values that will result in data being retrieved by the dataset.
Yet I am still getting the following errors when previewing the report; any advice or guidance would be most appreciated.
The report parameter ‘Resources’ has a DefaultValue or a ValidValue that depends on the report parameter “LanguageCode”. Forward dependencies are not valid.
The report parameter ‘Resources’ has a DefaultValue or a ValidValue that depends on the report parameter “ResourceNameLookup”. Forward dependencies are not valid.
I had the same error but it was due to something else. What I had done was created a Parameter in my report, then linked the Default Values to a Dataset.
This in turn added the parameters needed in the Dataset. Somehow, the order of the parameters in my list were changed. This is when I stared getting the 'Forward Dependencies are not Valid' error.
I then looked at another report that used the same process to link a Parameter to a Dataset. I noticed that the order of my Parameters were different. I simply went back to my new report, and used the up and down arrows until my Parameters were in the same order as the working report. This seemed to fix the error and work fine. Apparently the the Parameter that was using the Dataset needs to be below the Parameters that are used in the SPROC.
I this helps someone in the long run.
C/N: Parameter was being filled by a Dataset(Stored Procedure). The Parameter that was being filled was above some of the Parameters that it was expecting for the SPROC.
This was all caused by a stupid error I made. I copied and modified the code function from the post I mention but neglected to change the data type of the argument from integer to string, which mine is.
It seems rather odd that the error manifested in the way it did but I have gotten past that problem now, only to run into another that I ask about in another question.

Code not running when Field is NULL - SSRS 2005

I have a textbox in my SSRS 2005 report. The expresssion for this textbox is:
=IIF(IsDBNull(Fields!fOrgID), Code.SetMyVar("null"), Code.SetMyVar(Fields!fOrgID.Value))
I have also tried IsNothing(Fields!fOrgID) and a few other variations of checking for nulls.
I have modified the SetMyVar function for testing and it now looks like this:
Public Function SetMyVar (var as String)
MsgBox(var, VbOKCancel, "Test1")
If var Is Nothing Then
Return "NOTHING"
Else
MyVar = var
Return var
End If
End Function
I also have the public variable MyVar:
Public Shared Dim MyVar as String
When my database query returns data, this correctly evaluates, a messagebox is displayed with the value, the textbox gets set with the value, and the world is generally a happier place.
When my database query does not return a value though, I get the error:
The query returned no rows for the data set. The expression therefore
evaluates to null.
and the SetMyVar function never appears to be ran (you never get the messagebox popup). As expected, my emotions range from anger, sadness, and bitter hatred of SSRS.
I read something about SSRS evaluating both sides of an IF statement, so perhaps that is why I get the error (likely then on Code.SetMyVar(Fields!fOrgID.Value))... not sure how I get around that though.
Thoughts? Suggestions? Words of comfort?
From the sound of things, it seems likely that the issue is that SSRS is having a problem displaying zero records. I'd recommend one of the following:
1) Use a control that handles zero records appropriately (Tables do. I think Lists do as well).
2) Modify your query to return a single record with blank values if it would otherwise return zero records.
An answer to the original question:
=IIF(IsNothing(Fields!fOrgID),
Code.SetMyVar("null"),
Code.SetMyVar(IIF(IsNothing(Fields!fOrgID),"Foo",Fields!fOrgID.Value)))
The error was from both sides of IIF being evaluated. The extra IIF in the statement above will avoid Code.SetMyVar from ever being called with a null value.
I believe you're right about about Iif always evaluating both of its value arguments (at least, it does in Visual Basic). I'm not sure why you're getting this precise error (unless strings can't be assigned a value of DBNull?), but you almost certainly want to attack this problem with a different method.
The reason for this is that your current code will likely always call both set methods regardless of the conditional value.
Formula that worked for my SSRS 2008 reports.
=IIf(String.IsNullOrEmpty(Fields!NullableFieldwithPossibleBlankStrings.Value),"Yes","No")
I tried this too (also tried a version with IsNothing)...
=Code.SetField(IsDBNull(Fields!fOrgID))
And changed the function to be one that accepts a boolean. I figure this above function would always return a true or false, but in the event of a NULL, I again get "The query returned no rows for the data set. The expression therefore evaluates to null.".
I need to pass back to my code if the field is null or not (as this will let me know if the datasource is null or not).
Let me know if you can think of a better way because I cannot.