Infralution Support Forum Index Infralution Support
Support groups for Infralution products
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

FindUsingPrimaryKey returns -2

 
Post new topic   Reply to topic    Infralution Support Forum Index -> Virtual Data Objects Support
View previous topic :: View next topic  
Author Message
rp
Guest





PostPosted: Wed Dec 14, 2005 7:09 pm    Post subject: FindUsingPrimaryKey returns -2 Reply with quote

I switched the database my program is using from Access to Firebird, and everything has gone fine so far, except when I use the VirtualRecordSet.FindUsingPrimaryKey method it's returning -2.

The docs say it should return "-1" if the record isn't found. However, I've confirmed the record is there -- can you shed any light on this?
Back to top
Infralution



Joined: 28 Feb 2005
Posts: 4972

PostPosted: Wed Dec 14, 2005 10:06 pm    Post subject: Reply with quote

Below is the code that the FindUsingPrimaryKey method uses to locate the record in the recordset:

Code:

string criteria = String.Format("{0} = {1}", _primaryKey, GetPrimaryKeyString(primaryKeyValue));
Recordset rs = GetRecordset();
if (rs.RecordCount != 0)
{
    rs.MoveFirst();
    rs.Find(criteria, 0, SearchDirectionEnum.adSearchForward, Missing.Value);
}
return (rs.EOF) ? -1 : (int) rs.AbsolutePosition - 1;


where _primaryKey is the name of the primary key field you provided in the constructor for the recordset and GetPrimaryKeyString simply adds single quotes around text fields.

What is the database field type you have used as a primary key?

The only way I can see this function returning -2 is if the driver returned false for rs.EOF but -1 for rs.AbsolutePosition. This would be an inconsistency in the driver - but in any case would seem to indicate that the Find method did not succeed. You could test this out by connecting directly using ADODB to your firebird database and executing this same logic.
_________________
Infralution Support
Back to top
View user's profile Send private message Visit poster's website
rp
Guest





PostPosted: Wed Dec 14, 2005 11:26 pm    Post subject: Reply with quote

I've tried using INTEGER, BIGINT, and VARCHAR field types as the primary key. It doesn't appear to be the primary key field type causing this issue.

I think I may have found the problem. What cursor types and cursor locations does VDO support?

It appears the default cursor type and location setup for VDO is:

adUseServer
adOpenKeySet

Which the Firebird ODBC driver appears to have forced to:

adUseServer
adForwardOnly

Which in turn caused a freshly created Recordset object to do this:

Recordset.RecordCount returns -1
Recordset.AbsolutePosition returns adPosUnknown (I'm guessing this equals -1)
Recordset.EOF return False

Your code should probably check for this situation, and possibly throw an exception stating "ForwardOnly" cursors aren't supported instead of returning -2.

I think I found a workaround to this by setting the cursor location on the ADODB Connection object to adUseClient, and leaving the cursor type set to the default, adOpenKeyset. RecordCount seems to be returning correct values now.

Thank you for the clues!
Back to top
Display posts from previous:   
Post new topic   Reply to topic    Infralution Support Forum Index -> Virtual Data Objects Support All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group