Help needed with selection formula - joined tables

I have two tables, tblCustomers and tblVisitDate. The CustID field is a unique key in tblCustomers. The CustID field is used to identify the customer in each entry in the tblVisitDate table.

I want to select only the customer records in tblCustomers that have an entry in tblVisitDate matching a specific criteria. Also, I only want to select that record one time (I'm printing mailing labels).

I can perform this function in SQL using the IN and WITH keywords, but I don't know where to start with the CR selection formulas. Any help is appreciated- plus I would also appreciate a link to some online resources that explain how to write formulas.

Thanks in advance!

Some links - hope they help.

http://www.kenhamady.com/form00.shtml

http://www.crystalreportsbook.com/Chapter05_XI.asp

http://www.crystalreportsbook.com/Chapter06_XI.asp

http://www.willydev.net/InsiteCreati...orformulas.pdf

These links have a lot of information I didn't have access to before, and I will print a couple of them out for reference. However, I don't think they have what I need with respect to selecting parent records based on child entries.

I've been playing around with the codce, and here's what I've got so far:

Code:

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{tblCustomers.CustID} = ({tblDateVisited.CustID} WHERE {tblDateVisited.PlayerType} = {?PlayerType})

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I keep getting a missing ')' error following the WHERE keyword. I'm assuming that WHERE is not a valid keyword in these formulas, but I don't know what else to use. I've also tried something using IN which is a valid keyword, but I don't know the proper syntax, I think.

The Record Selection formula would simply be

{tblDateVisited.PlayerType} = {?PlayerType}

The link between the two tables can be created by using the Visual Linking Expert (note i use Crystal 8.5, no idea if the Linking Expert still applies to later versions).

Okay, I've tried the simple approach, but I'm still not seeing any results in the report.

I think I may have a new problem now. When I set the data source for the report in my VB code, I use the following syntax:

Code:

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Me.ReportFile.SetDataSource(DsSrchCustRpt.Tables(0))

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In other reports I only use one table to draw data from, but in the situation I'm currently working on there are three tables that the report pulls data from. I think my inability to assign data from the other three sources is the problem. How do you designate the data source for three tables?