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Q162072: FIX: SELECT - SQL from Table with 252 Fields Causes Page Fault

Article: Q162072
Product(s): Microsoft FoxPro
Version(s): WINDOWS:5.0
Operating System(s): 
Keyword(s): kbprogramming kbvfp kbvfp500aFIXkbbuglist kbfixlist
Last Modified: 04-FEB-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, version 5.0 
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SYMPTOMS
========

Issuing a SELECT - SQL statement using a table that has more than 251 fields may
cause Visual FoxPro to terminate with an Invalid Page Fault.

NOTE: This behavior has been duplicated with as few as 190 fields under a variety
of conditions (projects open, variables in memory, and so forth). The exact
number of fields that causes this behavior may vary.

RESOLUTION
==========

The workaround to the Invalid Page Fault is to perform the SQL SELECT as
identified in the second and third SELECT statements in the "Steps to Reproduce
Behavior" section below.

     SELECT *, .T. FROM <table>

-or-

     SELECT * FROM <table> INTO CURSOR <cursorname> NOFILTER

STATUS
======

This problem has been fixed in Visual FoxPro 5.0a.

MORE INFORMATION
================

Issuing a SELECT - SQL statement using a table that has more than 251 fields may
cause Visual FoxPro to terminate with an Invalid Page Fault. The following code
creates a table with 252 fields, inserts a single record, and performs three
different SQL SELECT statements. Generally, the first SELECT statement causes an
Invalid Page Fault.

Steps to Reproduce Behavior
---------------------------

Create and run a program with the following code:

      fldlist="("
     FOR i = 1 TO 251
          fldlist=fldlist+"fld"+ALLTRIM(STR(i))+" C(5),"
     ENDFOR

     fldlist=fldlist+"FLD"+ALLTRIM(STR(i))+" C(5))"

     valuelst=""
     valuelst=valuelst+REPLICATE("'"+'DATA'+"', ",i-1)+"'DATA'"

     CREATE TABLE manyflds FREE &fldlist
     INSERT INTO manyflds VALUES (&valuelst)

     SELECT * FROM manyflds        && Causes an Invalid Page Fault in VFP 5
     SELECT *,.T. FROM manyflds    && Works fine
     SELECT * FROM manyflds INTO CURSOR temp NOFILTER  && Works fine

Additional query words:

======================================================================
Keywords          : kbprogramming kbvfp kbvfp500aFIX kbbuglist kbfixlist
Technology        : kbVFPsearch kbAudDeveloper kbVFP500
Version           : WINDOWS:5.0
Issue type        : kbbug
Solution Type     : kbfix

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