Knowledge Base

FIX: COPY TO ... TYPE SDF Incorrectly Copies Null Fields

Article ID: 161054

Article Last Modified on 10/15/2003

Microsoft Visual FoxPro 3.0 Standard Edition
Microsoft Visual FoxPro 3.0b Standard Edition
Microsoft Visual FoxPro 5.0 Standard Edition

This article was previously published under Q161054

SYMPTOMS

The COPY TO <filename> TYPE SDF does not properly copy null type fields. The null fields do not appear in the output text file. The null fields in the SDF file have a zero width.

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. This problem has been fixed in Visual FoxPro 5.0a.

MORE INFORMATION

The following program illustrates this behavior.

Steps to Reproduce Behavior

Create a program containing the following code and execute it:

   CREATE CURSOR test (C1 C(5) NULL, C2 C(5) NULL, C3 C(5) NULL, C4 C(5);
   NULL)
   FOR i=1 TO 10
      IF MOD(i,2)=0
         INSERT INTO test (C1,C2,C3,C4) VALUES ('AAAAA',NULL,'CCCCC',NULL)
      ELSE
         INSERT INTO test (C1,C2,C3,C4) VALUES (NULL,'BBBBB',NULL,'DDDDD')
      ENDIF
   ENDFOR
   BROWSE

Close the Browse window and type the following commands in the Command window:
```
   COPY TO Test.txt TYPE SDF
   MODI COMM Test.txt
						
```
Notice the null fields from the cursor are not present in the SDF text file.

Keywords: kbbug kbfix kbvfp500afix kbprogramming KB161054