DOCUMENT:Q180193  04-FEB-1998  [vbwin]
TITLE   :PRB: DAO Oracle and the NUMBER Datatype
PRODUCT :Microsoft Visual Basic for Windows
PROD/VER:WINDOWS:5.0
OPER/SYS:WINDOWS
KEYWORDS:vb5all

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The information in this article applies to:

 - Microsoft Visual Basic Enterprise Edition for Windows, version 5.0
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SYMPTOMS
========

When using DAO/Jet to access an Oracle database, you get either blank rows
back in a grid or rows filled with #DEFINE (when using Access).

CAUSE
=====

This behavior is caused by DAO having a problem determining the datatype
for Oracle columns defined as NUMBER.

RESOLUTION
==========

This behavior is only exhibited when the Oracle columns have been defined
as NUMBER. If you define the columns as NUMBER(38,0), which is the
equivalent of just NUMBER, everything works as expected. When you use
DAO/Jet to access an Oracle database, you need to specify the size (total
digits) and precision for table columns of type NUMBER.

STATUS
======

Microsoft is researching this problem and will post new information here in
the Microsoft Knowledge Base as it becomes available.

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

This problem was identified using Visual Basic 5.0 Enterprise edition, MDAC
1.5 (see the REFERENCES section below), and Oracle 7.3. You may see
different behavior with different versions of these components. Following
is an example of what will work and what will fail when creating an Oracle
table that will be accessed by DAO/Jet.

This Oracle table definition will fail:

      CREATE TABLE daotest (item_number NUMBER PRIMARY KEY,
                            depot_number NUMBER);

This Oracle table definition will work:

      CREATE TABLE daotest (item_number NUMBER(38,0) PRIMARY KEY,
                            depot_number NUMBER(38,0));

If you are using Access, the first example will fill your grid with
#DELETE. If you are using Visual Basic/DAO, your grid will show the correct
number of rows but they won't contain any data. You can still insert
records but you never get the correct display.

REFERENCES
==========

ORACLE: The Complete Reference by George Koch and Kevin Loney

For additional information, please see the following article in the
Microsoft Knowledge Base:

   ARTICLE-ID: Q175018
   TITLE     : HOWTO: Acquire and Install the Microsoft Oracle ODBC Driver
               v2.0

(c) Microsoft Corporation 1998, All Rights Reserved.
Contributions by Sam Carpenter, Microsoft Corporation

Additional query words: DAO Jet Oracle grid #Define
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Keywords          : vb5all
Technology        : dao
Version           : WINDOWS:5.0
Platform          : WINDOWS
Issue type        : kbprb

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