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Is this a MFC/DAO bug???


Di Luo -- photosoft@monmouth.com
Tuesday, December 03, 1996

Environment:  VC++ 4.2b, Win 95

Is this a MFC/DAO bug???

I use MFC Application Wizard to create a project with the "Database with file 
support" option, and then just add the following code into the view's OnDraw():

	CString strSQL;
	strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts"); 
	CDaoQueryDef qd(m_pSet->m_pDatabase);
	qd.Create(NULL, (LPCTSTR)strSQL);
	try
	{
		if(m_pSet->IsOpen())
			m_pSet->Close();
		
		m_pSet->Open(&qd);
	}
	catch(CDaoException *e)
	{
		......
	}
 
What I am trying  to  do is to execute a  simple SQL to retrieve distinct last name  
from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM Contacts" 
(Contacts is MS ACCESS sample table). it fails with following message:
 "GetRows failed. The requested column is not a member of this recordset".
I have tried using both table or Dynaset RecordSet type. 

However if I use "SELECT * FROM Contacts", It works fine. 
I also tested the SQL from Access directly with no problem.

It seems to me it is MFC/DAO bug. Does anybody have similar experience?  


Thanks

Di Luo


Mike Blaszczak -- mikeblas@nwlink.com
Thursday, December 05, 1996

[Mini-digest: 9 responses]

At 12:22 12/3/96 -0800, Di Luo wrote:
>Environment:  VC++ 4.2b, Win 95

>Is this a MFC/DAO bug???

I don't think it is, but you've not provided enough information to decide
either way.

>(Contacts is MS ACCESS sample table). it fails with following message:
> "GetRows failed. The requested column is not a member of this recordset".

You need to show what list of columns are in the DoFieldExchange() function
of your recordset.  It seems to me that you're naming lots of fields in
there, even though you're only selecting one field with your smaller
SELECT statement.

.B ekiM
http://www.nwlink.com/~mikeblas/
I'm afraid I've become some sort of speed freak.
These words are my own. I do not speak on behalf of Microsoft.

-----From: Paul Armstrong 

try "SELECT DISTINCT LastName FROM Contacts" as your query.

----------
From: 	Di Luo[SMTP:photosoft@monmouth.com]
Sent: 	Tuesday, December 03, 1996 3:22 PM
To: 	mfc-l@netcom.com
Subject: 	Is this a MFC/DAO bug???

Environment:  VC++ 4.2b, Win 95

Is this a MFC/DAO bug???

I use MFC Application Wizard to create a project with the "Database with file 
support" option, and then just add the following code into the view's OnDraw():

	CString strSQL;
	strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts"); 
	CDaoQueryDef qd(m_pSet->m_pDatabase);
	qd.Create(NULL, (LPCTSTR)strSQL);
	try
	{
		if(m_pSet->IsOpen())
			m_pSet->Close();
		
		m_pSet->Open(&qd);
	}
	catch(CDaoException *e)
	{
		......
	}
 
What I am trying  to  do is to execute a  simple SQL to retrieve distinct last name  
from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM Contacts" 
(Contacts is MS ACCESS sample table). it fails with following message:
 "GetRows failed. The requested column is not a member of this recordset".
I have tried using both table or Dynaset RecordSet type. 

However if I use "SELECT * FROM Contacts", It works fine. 
I also tested the SQL from Access directly with no problem.

It seems to me it is MFC/DAO bug. Does anybody have similar experience?  


Thanks

Di Luo



-----From: Tom Allen 

I doubt if it is an MFC or DAO bug.  What happens if you remove the =
table qualifier from the column name and/or wrap brackets [ ] around the =
column name?   e.g.:

	"SELECT DISTINCT LastName from Contacts"
or
	"SELECT DISTINCT [LastName] from Contacts"

-TA
----------
From: 	Di Luo[SMTP:photosoft@monmouth.com]
Sent: 	Tuesday, December 03, 1996 3:22 PM
To: 	mfc-l@netcom.com
Subject: 	Is this a MFC/DAO bug???

Environment:  VC++ 4.2b, Win 95

Is this a MFC/DAO bug???

I use MFC Application Wizard to create a project with the "Database with =
file=20
support" option, and then just add the following code into the view's =
OnDraw():

	CString strSQL;
	strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts");=20
	CDaoQueryDef qd(m_pSet->m_pDatabase);
	qd.Create(NULL, (LPCTSTR)strSQL);
	try
	{
		if(m_pSet->IsOpen())
			m_pSet->Close();
	=09
		m_pSet->Open(&qd);
	}
	catch(CDaoException *e)
	{
		......
	}
=20
What I am trying  to  do is to execute a  simple SQL to retrieve =
distinct last name =20
from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM =
Contacts"=20
(Contacts is MS ACCESS sample table). it fails with following message:
 "GetRows failed. The requested column is not a member of this =
recordset".
I have tried using both table or Dynaset RecordSet type.=20

However if I use "SELECT * FROM Contacts", It works fine.=20
I also tested the SQL from Access directly with no problem.

It seems to me it is MFC/DAO bug. Does anybody have similar experience?  =



Thanks

Di Luo


-----From: George Grant 

I think I know your problem, I ran across something like it a while =
back. Your query:

SELECT DISTINCT Contacts.LastName FROM Contacts

should be:

SELECT DISTINCT LastName FROM Contacts

The problem is that JET only prefixes the table name when there is a =
naming conflict between two or more columns as the result of a join, =
etc.

Hope that helps...
-George


----------
From: 	Di Luo[SMTP:photosoft@monmouth.com]
Sent: 	Tuesday, December 03, 1996 12:22 PM
To: 	mfc-l@netcom.com
Subject: 	Is this a MFC/DAO bug???

Environment:  VC++ 4.2b, Win 95

Is this a MFC/DAO bug???

I use MFC Application Wizard to create a project with the "Database with =
file=20
support" option, and then just add the following code into the view's =
OnDraw():

	CString strSQL;
	strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts");=20
	CDaoQueryDef qd(m_pSet->m_pDatabase);
	qd.Create(NULL, (LPCTSTR)strSQL);
	try
	{
		if(m_pSet->IsOpen())
			m_pSet->Close();
	=09
		m_pSet->Open(&qd);
	}
	catch(CDaoException *e)
	{
		......
	}
=20
What I am trying  to  do is to execute a  simple SQL to retrieve =
distinct last name =20
from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM =
Contacts"=20
(Contacts is MS ACCESS sample table). it fails with following message:
 "GetRows failed. The requested column is not a member of this =
recordset".
I have tried using both table or Dynaset RecordSet type.=20

However if I use "SELECT * FROM Contacts", It works fine.=20
I also tested the SQL from Access directly with no problem.

It seems to me it is MFC/DAO bug. Does anybody have similar experience?  =



Thanks

Di Luo

-----From: tcatchick@aesprodata.com.au


     hi Di Luo
     
     If Contacts is the table name and LastName a field in this table then 
     as your SQL string statement try just using LastName without using the 
     alias 
     
     Regards
     
     Theron. C.


______________________________ Reply Separator _________________________________
Subject: Is this a MFC/DAO bug???
Author:  mfc-l@netcom.com at INTERNET
Date:    06/12/96 15:16


Environment:  VC++ 4.2b, Win 95
     
Is this a MFC/DAO bug???
     
I use MFC Application Wizard to create a project with the "Database with file 
support" option, and then just add the following code into the view's OnDraw():
     
 CString strSQL;
 strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts"); 
 CDaoQueryDef qd(m_pSet->m_pDatabase);
 qd.Create(NULL, (LPCTSTR)strSQL);
 try
 {
  if(m_pSet->IsOpen())
   m_pSet->Close();
     
  m_pSet->Open(&qd);
 }
 catch(CDaoException *e)
 {
  ......
 }
     
What I am trying  to  do is to execute a  simple SQL to retrieve distinct last 
na me  
from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM 
Contacts " 
(Contacts is MS ACCESS sample table). it fails with following message:
 "GetRows failed. The requested column is not a member of this recordset".
I have tried using both table or Dynaset RecordSet type. 
     
However if I use "SELECT * FROM Contacts", It works fine. 
I also tested the SQL from Access directly with no problem.
     
It seems to me it is MFC/DAO bug. Does anybody have similar experience?  
     
     
Thanks
     
Di Luo
-----From: "P. Senthil" 

Di Luo wrote:
> 
>                        Postage paid by: [Image]
> 
>     ---------------------------------------------------------------
> 
> Environment:  VC++ 4.2b, Win 95
> 
> Is this a MFC/DAO bug???
> 
> I use MFC Application Wizard to create a project with the "Database with file
> support" option, and then just add the following code into the view's OnDraw():
> 
>         CString strSQL;
>         strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts");
>         CDaoQueryDef qd(m_pSet->m_pDatabase);
>         qd.Create(NULL, (LPCTSTR)strSQL);
>         try
>         {
>                 if(m_pSet->IsOpen())
>                         m_pSet->Close();
> 
>                 m_pSet->Open(&qd);
>         }
>         catch(CDaoException *e)
>         {
>                 ......
>         }
> 
> What I am trying  to  do is to execute a  simple SQL to retrieve distinct last name
> from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM Contacts"
> (Contacts is MS ACCESS sample table). it fails with following message:
>  "GetRows failed. The requested column is not a member of this recordset".
> I have tried using both table or Dynaset RecordSet type.
> 
> However if I use "SELECT * FROM Contacts", It works fine.
> I also tested the SQL from Access directly with no problem.
> 
> It seems to me it is MFC/DAO bug. Does anybody have similar experience?
> 
> Thanks
> 
> Di Luo

This usually happens if the number of columns in the SQL Query does not
match the columns specified in the dynaset or recordset. Unfortunately,
a single recordset or dynaset cannot be used for retrieving only a
subset of the selected columns, you have to use a different recordset
for that.

P. Senthil
---------------------------------------------------
Mail: senthilp@geocities.com
WWW:  www.geocities.com/SiliconValley/Heights/6504/
---------------------------------------------------
-----From: Rogas 

Di Luo wrote:
> 
> Environment:  VC++ 4.2b, Win 95
> 
> Is this a MFC/DAO bug???
> 
> I use MFC Application Wizard to create a project with the "Database with file
> support" option, and then just add the following code into the view's OnDraw():
> 
>         CString strSQL;
>         strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts");
>         CDaoQueryDef qd(m_pSet->m_pDatabase);
>         qd.Create(NULL, (LPCTSTR)strSQL);
>         try
>         {
>                 if(m_pSet->IsOpen())
>                         m_pSet->Close();
> 
>                 m_pSet->Open(&qd);
>         }
>         catch(CDaoException *e)
>         {
>                 ......
>         }
> 
> What I am trying  to  do is to execute a  simple SQL to retrieve distinct last name
> from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM Contacts"
> (Contacts is MS ACCESS sample table). it fails with following message:
>  "GetRows failed. The requested column is not a member of this recordset".
> I have tried using both table or Dynaset RecordSet type.
> 
> However if I use "SELECT * FROM Contacts", It works fine.
> I also tested the SQL from Access directly with no problem.
> 
> It seems to me it is MFC/DAO bug. Does anybody have similar experience?
> 
> Thanks
> 
> Di Luo
Hi

I am developing an application that uses DAO and I had such problems.
You must check very carefully if you have all column names typed
correctly. Besides I would try
"SELECT DISTINCT LastName FROM Contacts" instead of your
"Contacts.LastName".
Then it should work.
Here are some queries of my program:

"SELECT F.IDfond, F.nom, \
fut_larg, fut_haut, fut_dispY, semelle_larg, semelle_haut \
FROM fondation AS F \
WHERE F.public<>0 \
AND F.nom=\""+ szName +"\";"

"SELECT A.IDass, A.nom \
FROM assemblage AS A \
WHERE A.public<>0 \
AND nom=\""+ szName +"\";"

"SELECT A.IDass, A.nom, A.type, R2.IDmontant1, \
R2.IDmontant2, R2.nr_queue, R2.position \
FROM structure AS S, assemblage AS A, Rstruct_ass AS R2 \
WHERE  A.IDass=R2.IDass \
  AND S.IDstruct=R2.IDstruct \
  AND S.IDstruct=" + CString(idstr) + " \
ORDER BY R2.nr_queue;"

szName and idstr are parameters to query I pass.

Hope you find it useful

Rogas
-----From: Mast-CBT 

At 12.22 03/12/96 -0800, you wrote:
>Environment:  VC++ 4.2b, Win 95
>
>Is this a MFC/DAO bug???
>
>I use MFC Application Wizard to create a project with the "Database with file 
>support" option, and then just add the following code into the view's OnDraw():
>
>	CString strSQL;
>	strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts"); 
>	CDaoQueryDef qd(m_pSet->m_pDatabase);
>	qd.Create(NULL, (LPCTSTR)strSQL);
>	try
>	{
>		if(m_pSet->IsOpen())
>			m_pSet->Close();
>		
>		m_pSet->Open(&qd);
>	}
>	catch(CDaoException *e)
>	{
>		......
>	}
> 
>What I am trying  to  do is to execute a  simple SQL to retrieve distinct
last name  
>from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM
Contacts" 
>(Contacts is MS ACCESS sample table). it fails with following message:
> "GetRows failed. The requested column is not a member of this recordset".
>I have tried using both table or Dynaset RecordSet type. 
>
>However if I use "SELECT * FROM Contacts", It works fine. 
>I also tested the SQL from Access directly with no problem.
>
>It seems to me it is MFC/DAO bug. Does anybody have similar experience?  
>
>
>Thanks
>
>Di Luo
>
>

For this problem you can see article ID:Q139994 about:
'Specifying Table Name with Column Name in MFC DAO'.

Search in Microsoft site 'www.microsoft.com', Microsoft Support, Knowledge Base.

I hope this help you.

Bye
Fabio
--------------------------------------------------
Fabio Saponaro
Context Systems Group  -   Italian Branch
Magenta (MI)

Tel. ++ 39 2 97298145
Fax  ++ 39 2 97298225

http://www.web.csg.it
--------------------------------------------------


-----From: "Michael Potter" 

I think you are missing a call to 
	qd.Append().

Or you can skip the qd all together and pass the strSQL to the
m_pSet->Open() method.

Mike 

----------
> From: Di Luo 
> To: mfc-l@netcom.com
> Subject: Is this a MFC/DAO bug???
> Date: Tuesday, December 03, 1996 2:22 PM
> 
> Environment:  VC++ 4.2b, Win 95
> 
> Is this a MFC/DAO bug???
> 
> I use MFC Application Wizard to create a project with the "Database with
file 
> support" option, and then just add the following code into the view's
OnDraw():
> 
> 	CString strSQL;
> 	strSQL.Format("SELECT DISTINCT Contacts.LastName FROM Contacts"); 
> 	CDaoQueryDef qd(m_pSet->m_pDatabase);
> 	qd.Create(NULL, (LPCTSTR)strSQL);
> 	try
> 	{
> 		if(m_pSet->IsOpen())
> 			m_pSet->Close();
> 		
> 		m_pSet->Open(&qd);
> 	}
> 	catch(CDaoException *e)
> 	{
> 		......
> 	}
>  
> What I am trying  to  do is to execute a  simple SQL to retrieve distinct
last name  
> from the table Contacts by using "SELECT DISTINCT Contacts.LastName FROM
Contacts" 
> (Contacts is MS ACCESS sample table). it fails with following message:
>  "GetRows failed. The requested column is not a member of this
recordset".
> I have tried using both table or Dynaset RecordSet type. 
> 
> However if I use "SELECT * FROM Contacts", It works fine. 
> I also tested the SQL from Access directly with no problem.
> 
> It seems to me it is MFC/DAO bug. Does anybody have similar experience?  
> 
> 
> Thanks
> 
> Di Luo

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