Solved

ADO corrupts date time values in where clause

Posted on 2006-11-16
7
478 Views
Last Modified: 2008-01-09
We have a propreitary application similar to VB that uses ADO for talking to an Oracle database. We use ORaoledb.oracle as the provider.

At times we are getting error messages like "Row cannot be located for updating" and sometimes ORA-01841 Invalid date.

This error does not happen to all the users. But once it starts occuring for a user, it's persistent till the time user logs out and logs back into the application.

We were able to do an oracle trace and identify the sql statements that were causing this.

In some cases we see that the year component of a date field in the where clause being chopped off. This happens only in fields where date is 30-DEC-1899.
(ie) instead of passing 1899-12-30 09:30:00 it passes -12-30 09:30:00. This throws the invalid date format error.

Also in some cases the time component seems to be offset by 10 secs (ie) In the database if the time component of a date field is 00:00:00, ado passes 00:00:10 in the where clause. Thus causing the unable to locate row error.

Now all these are in the where clause.Since the where clause is something that ADO builds, we are at a loss as to what's going on.

The values for the same fields (used in the set protion of the update) passed from the application are in correct format.

Any ideas or thoughts welcome.
0
Comment
Question by:sathyagiri
  • 3
  • 3
7 Comments
 
LVL 14

Author Comment

by:sathyagiri
Comment Utility
Also is there a way to trace the ADO calls?
0
 
LVL 14

Expert Comment

by:Shiju Sasidharan
Comment Utility
What is the data type of that table field?

Also try to post the portion of your code where you actually build the where clause
0
 
LVL 14

Author Comment

by:sathyagiri
Comment Utility
The application does not build the where clause. We just select a record and modify the values and call ADO UPDATE.

ADO seems to be generating the where clause with all the columns in the table.
0
Highfive + Dolby Voice = No More Audio Complaints!

Poor audio quality is one of the top reasons people don’t use video conferencing. Get the crispest, clearest audio powered by Dolby Voice in every meeting. Highfive and Dolby Voice deliver the best video conferencing and audio experience for every meeting and every room.

 
LVL 14

Expert Comment

by:Shiju Sasidharan
Comment Utility
>>The application does not build the where clause
Please provide the SQL code segment you are using. This will be helpful for us to debug
0
 
LVL 14

Author Comment

by:sathyagiri
Comment Utility
Here's what we do

ADO select * from table where <condition>

ADO FINDFIRST <table>

-- Set new values here
ADO UPDATE <context> ALL

0
 
LVL 5

Accepted Solution

by:
RainUK earned 500 total points
Comment Utility
"Row cannot be located for updating"  - The error you are getting usually comes from when you select a set of rows and whilst you are reading and modifying them in your version of the cursor, somebody else makes an update to the rows you have selected.

Hence when you go to update them you get the error that the rows cannot be found for updating.

Basically the (Row Version) property in ADO has changed since you last read the rows because somebody else has updated or deleted the rows in the DB.

As for the date thing, not sure what your code does to update the date, but you can format the date in either VB6 or T-SQL into a certain format before updating it.
0
 
LVL 14

Expert Comment

by:Shiju Sasidharan
Comment Utility
>>ADO UPDATE <context> ALL

simply seeing the algorithm we can not predict the exact error.
Please try to post the exact source code segment for the same
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

Suggested Solutions

There are many ways to remove duplicate entries in an SQL or Access database. Most make you temporarily insert an ID field, make a temp table and copy data back and forth, and/or are slow. Here is an easy way in VB6 using ADO to remove duplicate row…
Introduction While answering a recent question about filtering a custom class collection, I realized that this could be accomplished with very little code by using the ScriptControl (SC) library.  This article will introduce you to the SC library a…
Get people started with the process of using Access VBA to control Outlook using automation, Microsoft Access can control other applications. An example is the ability to programmatically talk to Microsoft Outlook. Using automation, an Access applic…
Get people started with the process of using Access VBA to control Excel using automation, Microsoft Access can control other applications. An example is the ability to programmatically talk to Excel. Using automation, an Access application can laun…

771 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

14 Experts available now in Live!

Get 1:1 Help Now