About sub dataset and connection expression

[binmaker]

Hi, everyone.

Let me show you a example for your understanding. A report what I like to make has a page header, a detail, a page footer.

I'm gonna place a title and student information, such as a name, an address, an age and so on, on a page header. I'll also place lecture list that the student is taking on a detail band. Finally I'll place school information on a page footer band.

For this report, I've got to use three queries. The first one is for student information and second query is for lecture list and the last is for school information.

The first problem is I have to use two database servers, It means I have to use two connection information.

I aleady tried to use a sub report for school information. From what I know, I've got to pass connection information from a master report to a sub report if a sub report doesn't use same connection with a master report. But I couldn't solve connection expression problem, because I don't know how to set a connection expression of a sub report.

The last thing what I want to know is related with a sub dataset. In this sample, I used a sub dataset for student information. Before I know about a sub dataset, I used a sub report. But after knowing about that, I wanted to use a sub dataset. But when I used that, the report gave me some errors. The errors said there wasn't speicified fields. And I also have another question about a sub dataset, that is how I can make a relation between a parameter of master report and a parameter of sub dataset.

If you might know the answer to above questions, let me know, please.

Thanks in advance.

P.S. iReport 3.7