Help Me!! Calculate and formula in Crystal Report 6

[UJ]

I must do a report by crystal report6 about testing result that concerns 4 tables as follows:<br>1. Product table =&gt; ID, Name, …..(other details of product)<br>Eg. F102 Bead wire02<br><br>2. Specification =&gt;&nbsp;&nbsp;Table that keep specification of each product<br>Effect_date : effective date for this product (mm/dd/yyyy)<br>Product_ID : id that links to product table <br>Aname: Type of analysis <br>Min: Minimum value<br>Target: Target value<br>Max: Max value<br>XXXX = Aname in specification<br>Test value = Value of testing<br><br>Eg.&nbsp;&nbsp;<br>Effect_date-----Product_ID------Aname--------------Min----Target---Max<br>06/1/2000-------F102-------------Rugosity-------------3.5---------5---------7<br>06/1/2000-------F102-------------Diameter -------------5----------7---------10<br>06/1/2000-------F102-------------WL---------------------2----------5---------7<br>06/1/2000-------F103-------------WL---------------------2----------8---------10<br>07/1/2000------F102--------------Rugosity--------------3--------- 5--------- 7<br><br>3. Production record<br>Ticket_no----Product_ID: --------Production_date&nbsp;&nbsp;&nbsp;…..other production detail <br>10005--------- F102------------------07/25/2000 <br>10006--------- F102------------------07/26/2000 <br>10007--------- F102------------------07/27/2000 <br><br>4. Test result <br>Ticket_NO: Ticket number in production line<br>Product_ID: id that links to product table<br>TestDate: Testing date<br>XXXXX1 :&nbsp;&nbsp;Test value<br>…….<br>XXXXXn: Test value<br>Eg.<br>Ticket No---------Product_ID --- ------TestDate----- Rugosity---------Diameter---------WL<br>1005---------F102------------------08/1/2000---------5------------------ 7------------------5<br>1006---------F102------------------08/1/2000---------6------------------7------------------5.5<br>1007---------F102------------------08/2/2000---------5------------------ 7------------------5<br> <br> <br>1. How I can get specification value of the product. The specification has constraint that the effective date &lt;= test date and it must be up to date specification.<br>2. How I can calculate min, avg, max value of&nbsp;&nbsp;ticket no 1005, 1006 and 1007<br><br>My designed report is….<br>Product ID: <br>Product Name: Bead wire02<br>Production date: 07/25/2000 – 07/27/2000<br>Number of product = 3<br><br>------------------------------------Test result----------------------------Specification<br>ITEMS--------------Min---------Avg---------Max-------------Min---------Avg---------Max<br>Rugosity-------------5---------5.33---------6------------------3------------5-------------7<br>Diameter----------- 7---------- 7------------7------------------ 5------------7------------10<br>WL------------------- 5---------5.16---------5.5----------------2-----------5--------------7<br>………….<br><br>&nbsp;<br>I can code in VB to show on listview control but I can’t do it in Crystal report.. what I can do<br>I would like to use parameter fields but it has a lot of fields (about 10-17 analysis in specification)<br>