PRB: Query to a Report Causes an Inaccurate Sum or Count

ID: Q120187

2.00 2.5x 2.60 2.60a | 2.5x 2.60 2.60a 3.00| 2.5x 2.60a | 2.60

MS-DOS               | WINDOWS             | MACINTOSH  | UNIX
 kbprb

- Microsoft Visual FoxPro for Windows, version 3.0 - Microsoft FoxPro for MS-DOS, versions 2.0, 2.5x, 2.6, 2.6a - Microsoft FoxPro for Windows, versions 2.5x, 2.6, 2.6a - Microsoft FoxPro for Macintosh, versions 2.5x, 2.6 - Microsoft FoxPro for UNIX, version 2.6

SYMPTOMS

When you are running a query to a report using two or more databases with a one-to-many relationship and the report is counting or performing other math functions on fields from the parent database, the count or value from the math functions is inaccurate.

RESOLUTION

To get an accurate count, you need to create a user-defined function (UDF). For an example of a UDF that produces the correct count, see "Workaround" in the "More Information" section below.

MORE INFORMATION

When the report performs a count or any math function, it looks to the source database for its information. If the data comes from a query, the source is a temporary table called QUERY. If the query had two or more tables in it with a one-to-many relationship, there will be a matching parent field for each child field.

Steps to Reproduce Problem

1. Use the CUSTOMER.DBF and INVOICES.DBF tables that are found in the

   <FoxPro_directory>\TUTORIAL subdirectory.

   INVOICES.INO, and INVOICES.ITOTAL fields. Just put the field names in
   the report and mark the fields coming from CUSTOMER so they don't print
   repeated values.

4. In the group footer band, place the CNO field and select Calculate and

   then Count.

6. Open a query and add the CUSTOMER and INVOICES tables.

7. Add the fields listed above to the fields list in the query.

8. Order the query by state.

9. Output the query to the report saved in step 5 above.

If you look at the group from the state of "GA", you will see that the count is 7 but that there are only four different companies.

Workaround

To obtain the correct count, you can use the following UDF.

   FUNCTION mycount
   PARAMETERS x
   recnum = RECNO()
   mygroup = state
   SELECT DISTINCT customer.cno, customer.state;
     FROM customer, invoices;
     WHERE invoices.cno = customer.cno;
     AND customer.state = mygroup;
     INTO CURSOR counter
   COUNT TO x
   SELECT QUERY
   GO recnum
   RETURN x

REFERENCES

FoxPro for Windows "Getting Started," Chapter 9 FoxPro for Windows and MS-DOS "Language Reference," page L3-1114

Additional reference words: VFoxWin 3.00 FoxUnix FoxMac FoxDos FoxWin 2.00 2.50 2.50a 2.50b 2.50c 2.60 2.60a KBCategory: kbprb KBSubcategory: FxprgGeneral

Keywords          : kbcode FxprgGeneral 
Version           : 2.00 2.5x 2.60 2.60a | 2.5x 2.60
Platform          : MACINTOSH MS-DOS UNIX WINDOWS