You are correct that the expression builder will let you select fields only from the dataset that is connected to the data region. You have to know the name of the field from the other dataset in order to use it in the Lookup function. I have successfully used this function with datasets that use different sources – which is the only time this technique makes sense to me because if they used the same source, I could use a join operation in the dataset query which would be preferable for better performance when working with large data volumes.

If you’re running into an error in Preview mode, then you might not have the right data type or something doesn’t match exactly between the fields that you are using to compare with one another in the first and second arguments of the Lookup function.

I tried to use the Lookup-Function in exactly this way.
I my case the Expression-Builder stops me from editing.
The table you use in Figure 2 to insert the expression, is connected to only one dataset (in your case Dataset1) as you can see in the Table/Tablix properties.
Fields used in the expression Builder can only be selected from this dataset (Dataset1). All other Fields (e.g. from the Dataset2) are not available and produce runtime errors( e.g. in the Preview). Is this because of the situation: the datasets are build on different Sources ?
There is something wrong in my scenario, because otherwise the Lookup-Function ( only for one Dataset ) makes no sense.

Any idea ?

Stefan

Having said all this, I’m “close” to a purely standalone environment running Win 7 and PowerPivot and SP2010. I’ve had to do several things manually (like running New-SPConfigurationDatabase, and then installing all the SP2010 pre-reqs manually). I was then able to run the SQL R2 setup to latch onto my existing SP farm – and it ran without errors and recognized the account I specified when I ran the SharePoint management shell.

I’m on the last set of steps, to configure the PPivot unattended account and the stored credentials. I smell a new blog entry!!!

Thanks,
Kevin

The single-machine installations which I referenced in my last reply are all server operating systems, so I was able to create a domain controller on those machines directly.

As far as I know, you won’t be able to create a standalone installation on a Windows 7 machine following the procedures I described. I’m glad you pointed that out to save others some grief before giving it a try if they don’t have a domain controller available elsewhere.

I wouldn’t have thought you could create a domain controller and a domain account on a standalone Windows 7 machine.

Right now, I have a complete R2 and SP2010 environment with PowerPivot/SP2010 integration – on a standalong machine running Windows Server. I’d love to do the same thing on a standalone Windows 7 machine….but I’m still not sure it’s possible. (Unless I try the Powershell trick)

Thanks….
Kevin

I don’t have an idea immediately. I’m in travel mode before the long weekend, but I’ll give it some thought next week. If I come up with a solution, I’ll let you know.

I think one thing that is lacking is that one can not add a calculated field to a dataset and call the same lookup function. When one does that then an error occurs stating that it can’t be done for scope purposes.

Do you know of a way to lookup information from another database and include it in a calculate field on a source dataset by a key code? If it is done at the data set level and not the table executing then one could do cool things like group/filter/sort by the new field.