DOCUMENT:Q69158  02-NOV-2001  [vbwin]
TITLE   :ISAMCVT Doesn't Properly Convert db/LIB Date Fields
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER::1.0,7.0,7.1
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Visual Basic for MS-DOS 1.0 
 - Microsoft Basic Professional Development System (PDS) for MS-DOS and MS OS/2, versions 7.0, 7.1 
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SYMPTOMS
========

Pages 148-149 of the "Microsoft Visual Basic for MS-DOS: Professional Edition
Features" manual states that the ISAMCVT utility will convert db/LIB date fields
to Basic double-precision numbers for use with the Date/Time add-on libraries.
This information is also listed on Page 393 of the "Microsoft Basic 7.0:
Programmer's Guide" (for versions 7.0 and 7.1).

ISAMCVT does convert a date field to a double-precision number, but the resulting
number is not a serial number that can be used with the date libraries included
with Visual Basic for MS-DOS, or Basic PDS.

STATUS
======

Microsoft has confirmed this to be a bug in the ISAMCVT.EXE utility for the
Professional Edition of Microsoft Visual Basic for MS-DOS, version 1.0, and for
Microsoft Basic Professional Development System (PDS) for MS-DOS, versions 7.0
(buglist7.00) and 7.1 (buglist7.10). We are researching this problem and will
post new information here in the Microsoft Knowledge Base as it becomes
available.

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

When ISAMCVT converts a date field, it converts it to a 8-byte string, but tags
it internally as a double. To see the string, you must use the MKD$ function to
convert the double to a string.

However, ISAMCVT also converts the year portion of the date incorrectly by
dropping the last two digits (for example, 1990 becomes 19, and 1890 becomes
18.)

For example, if you have a db/LIB file ("test.dbf") containing three fields and
one record

   NUMERIC (length=4, # decimals=1) = 1.2
   CHARACTER (length = 50) = My Name
   DATE = 19901214

and you convert it using the following command:

   " ISAMCVT /D test.dbf table test.mdb " (without the quotation marks)

The program listed below will then show that the ISAM file contains the
following:

   CustNum = 1.2
   Name = My Name
   Date = 12/14/19

Code Sample
-----------

NOTE: PROISAM.EXE must be loaded before running this program inside of VBDOS.EXE
or QBX.EXE.

   ' To try this example in VBDOS.EXE:
   ' 1. From the File menu, choose New Project.
   ' 2. Copy the code example to the Code window.
   ' 3. Press F5 to run the program.
   TYPE rectype
       CustNum AS DOUBLE
       Name AS STRING * 50
       Date AS DOUBLE
   END TYPE
   DIM a AS rectype
   OPEN "test.mdb" FOR ISAM rectype "table" AS #1
   SETINDEX #1, ""
   MOVEFIRST #1
   RETRIEVE #1, a
   PRINT a.CustNum
   PRINT a.Name
   PRINT MKD$(a.Date)
   CLOSE #1

Additional query words: VBmsdos BasicCom SR# S910116-88 buglist1.00 1.00 7.00 7.10

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Keywords          :  
Technology        : kbVBSearch kbAudDeveloper kbBASICSearch kbZNotKeyword3 kbBASICPDS700DOS kbBASICPDS710DOS kbBASICPDS700OS2 kbBASICPDS710OS2 kbVB100DOS
Version           : :1.0,7.0,7.1

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