ExecuteNonQuery

[Tony M]

Shouldn't the ExecuteNonQuery be TRUE if it finds a record and FALSE is not?
I get FALSE all the time and I seeded the database with the email address.
I just want to check if record exist before moving on.
If this doesn't work I guess I could load a datatable and check to see if
rows 0.


Dim cnString As OleDbConnection

cnString = New OleDbConnection ("Provider=Micr oSoft.Jet.OLEDB .4.0; Data
source = " & Server.MapPath( "Someplace.mdb" ))

Dim CheckCus As New OleDbCommand("S ELECT * from Cus where EMailAddress =" &
QM & Trim(txtEMail.T ext) & QM, cnString)


CheckCus.Connec tion.Open()

If CheckCus.Execut eNonQuery() Then
txtFirstName.Te xt = "Yes"
Else
txtFirstName.Te xt = "No " & Now
End If

CheckCus.Connec tion.Close()

Thanks
Tony

[Scott M.]

Re: ExecuteNonQuery

A SELECT statement is a query. You don't use ExecuteNonQuery when you are,
in fact, querying the database. Since your query *can* return results, you
need to use the ExecuteReader method of your command, which returns a
DataReader object that you then use to look at the query results.

Try this:

Try
Dim con As New OleDbConnection ("Provider=Micr oSoft.Jet.OLEDB .4.0; Data
Source = " & Server.MapPath( "Someplace.mdb" ))
Dim cmd As New OleDbCommand("S ELECT * from Cus where EMailAddress =" &
QM & Trim(txtEMail.T ext) & QM, cnString)
con.Open()

Dim dr As Oledb.OledbData Reader = cmd.ExecuteRead er()

If dr.HasRows Then
txtFirstName.Te xt = "Yes"
Else
txtFirstName.Te xt = "No " & Now
End If

Catch ex As Oledb.OledbExce ption
'Database exceptions handled here
Catch ex As Exception
'All other exceptions handled here
Finally
dr.Close()
con.Close()
con.Dispose()
End Try




"Tony M" <TonyMast_NOSPA M@msn.comwrote in message
news:e$v9PY8yHH A.5980@TK2MSFTN GP04.phx.gbl...

>
>
Shouldn't the ExecuteNonQuery be TRUE if it finds a record and FALSE is
not?
I get FALSE all the time and I seeded the database with the email address.
I just want to check if record exist before moving on.
If this doesn't work I guess I could load a datatable and check to see if
rows 0.
>
>
Dim cnString As OleDbConnection
>
cnString = New OleDbConnection ("Provider=Micr oSoft.Jet.OLEDB .4.0; Data
source = " & Server.MapPath( "Someplace.mdb" ))
>
Dim CheckCus As New OleDbCommand("S ELECT * from Cus where EMailAddress ="
& QM & Trim(txtEMail.T ext) & QM, cnString)
>
>
CheckCus.Connec tion.Open()
>
If CheckCus.Execut eNonQuery() Then
txtFirstName.Te xt = "Yes"
Else
txtFirstName.Te xt = "No " & Now
End If
>
CheckCus.Connec tion.Close()
>
Thanks
Tony
>

[=?ISO-8859-1?Q?G=F6ran_Andersson?=]

Re: ExecuteNonQuery

Tony M wrote:

Shouldn't the ExecuteNonQuery be TRUE if it finds a record and FALSE is not?
I get FALSE all the time and I seeded the database with the email address.
I just want to check if record exist before moving on.
If this doesn't work I guess I could load a datatable and check to see if
rows 0.
>
>
Dim cnString As OleDbConnection
>
cnString = New OleDbConnection ("Provider=Micr oSoft.Jet.OLEDB .4.0; Data
source = " & Server.MapPath( "Someplace.mdb" ))
>
Dim CheckCus As New OleDbCommand("S ELECT * from Cus where EMailAddress =" &
QM & Trim(txtEMail.T ext) & QM, cnString)
>
>
CheckCus.Connec tion.Open()
>
If CheckCus.Execut eNonQuery() Then
txtFirstName.Te xt = "Yes"
Else
txtFirstName.Te xt = "No " & Now
End If
>
CheckCus.Connec tion.Close()
>
Thanks
Tony
>

The method doesn't return a boolean at all, it returns an integer. If
you would have use Option Strict the compiler would have told you that.

The return value is the number of affected records. As a select query
never changes any records, your call will always return zero.

--
Göran Andersson
_____

http://www.guffa.com

[Tony M]

Re: ExecuteNonQuery

Thanks to all.
seems like allot of work just to see if a record exist, but it works.

Thanks again

"Scott M." <s-mar@nospam.nosp amwrote in message
news:OHIZ3k8yHH A.2224@TK2MSFTN GP02.phx.gbl...

>A SELECT statement is a query. You don't use ExecuteNonQuery when you are,
>in fact, querying the database. Since your query *can* return results, you
>need to use the ExecuteReader method of your command, which returns a
>DataReader object that you then use to look at the query results.
>
Try this:
>
Try
Dim con As New OleDbConnection ("Provider=Micr oSoft.Jet.OLEDB .4.0; Data
Source = " & Server.MapPath( "Someplace.mdb" ))
Dim cmd As New OleDbCommand("S ELECT * from Cus where EMailAddress =" &
QM & Trim(txtEMail.T ext) & QM, cnString)
con.Open()
>
Dim dr As Oledb.OledbData Reader = cmd.ExecuteRead er()
>
If dr.HasRows Then
txtFirstName.Te xt = "Yes"
Else
txtFirstName.Te xt = "No " & Now
End If
>
Catch ex As Oledb.OledbExce ption
'Database exceptions handled here
Catch ex As Exception
'All other exceptions handled here
Finally
dr.Close()
con.Close()
con.Dispose()
End Try
>
>
>
>
"Tony M" <TonyMast_NOSPA M@msn.comwrote in message
news:e$v9PY8yHH A.5980@TK2MSFTN GP04.phx.gbl...

>>
>>
>Shouldn't the ExecuteNonQuery be TRUE if it finds a record and FALSE is
>not?
>I get FALSE all the time and I seeded the database with the email
>address.
>I just want to check if record exist before moving on.
>If this doesn't work I guess I could load a datatable and check to see if
>rows 0.
>>
>>
>Dim cnString As OleDbConnection
>>
>cnString = New OleDbConnection ("Provider=Micr oSoft.Jet.OLEDB .4.0; Data
>source = " & Server.MapPath( "Someplace.mdb" ))
>>
>Dim CheckCus As New OleDbCommand("S ELECT * from Cus where EMailAddress ="
>& QM & Trim(txtEMail.T ext) & QM, cnString)
>>
>>
>CheckCus.Conne ction.Open()
>>
>If CheckCus.Execut eNonQuery() Then
> txtFirstName.Te xt = "Yes"
>Else
> txtFirstName.Te xt = "No " & Now
>End If
>>
>CheckCus.Conne ction.Close()
>>
>Thanks
>Tony
>>

>
>
>

[Spam Catcher]

Re: ExecuteNonQuery

"Tony M" <TonyMast_NOSPA M@msn.comwrote in
news:e$v9PY8yHH A.5980@TK2MSFTN GP04.phx.gbl:

Dim CheckCus As New OleDbCommand("S ELECT * from Cus where EMailAddress
=" & QM & Trim(txtEMail.T ext) & QM, cnString)

You should always use SQL Parameters for your queries. Otherwise you can be
the victim of a SQL injection attack.

[Johnny Jörgensen]

Re: ExecuteNonQuery

Gotta ask...

What the heck is a "SQL injection attack"?

Cheers,
Johnny J.




"Spam Catcher" <spamhoneypot@r ogers.comwrote in message
news:Xns99781AB 507DABusenethon eypotrogers@127 .0.0.1...

"Tony M" <TonyMast_NOSPA M@msn.comwrote in
news:e$v9PY8yHH A.5980@TK2MSFTN GP04.phx.gbl:
>

>Dim CheckCus As New OleDbCommand("S ELECT * from Cus where EMailAddress
>=" & QM & Trim(txtEMail.T ext) & QM, cnString)

>
You should always use SQL Parameters for your queries. Otherwise you can
be
the victim of a SQL injection attack.

[Spam Catcher]

Re: ExecuteNonQuery

"Johnny Jörgensen" <jojo@altcom.se wrote in
news:#NlQWlozHH A.4824@TK2MSFTN GP02.phx.gbl:

Gotta ask...
>
What the heck is a "SQL injection attack"?

http://en.wikipedia.org/wiki/SQL_injection

There are .NET examples in the wikipedia article.

[Scott M.]

Re: ExecuteNonQuery

Just remember Tony, that connecting to a database and querying it is one of
the most common things programmers do and it's one of the most common things
programmers do incorrectly or incompletely.

Putting your code inside of a Try...Catch and remembering to dispose of the
connection are essential to building robust database applications.

-Scott

"Tony M" <TonyMast_NOSPA M@msn.comwrote in message
news:eJ3JSTnzHH A.1484@TK2MSFTN GP06.phx.gbl...

Thanks to all.
seems like allot of work just to see if a record exist, but it works.
>
Thanks again
>
"Scott M." <s-mar@nospam.nosp amwrote in message
news:OHIZ3k8yHH A.2224@TK2MSFTN GP02.phx.gbl...

>>A SELECT statement is a query. You don't use ExecuteNonQuery when you
>>are, in fact, querying the database. Since your query *can* return
>>results, you need to use the ExecuteReader method of your command, which
>>returns a DataReader object that you then use to look at the query
>>results.
>>
>Try this:
>>
>Try
> Dim con As New OleDbConnection ("Provider=Micr oSoft.Jet.OLEDB .4.0; Data
>Source = " & Server.MapPath( "Someplace.mdb" ))
> Dim cmd As New OleDbCommand("S ELECT * from Cus where EMailAddress =" &
>QM & Trim(txtEMail.T ext) & QM, cnString)
> con.Open()
>>
> Dim dr As Oledb.OledbData Reader = cmd.ExecuteRead er()
>>
> If dr.HasRows Then
> txtFirstName.Te xt = "Yes"
> Else
> txtFirstName.Te xt = "No " & Now
> End If
>>
>Catch ex As Oledb.OledbExce ption
> 'Database exceptions handled here
>Catch ex As Exception
> 'All other exceptions handled here
>Finally
> dr.Close()
> con.Close()
> con.Dispose()
>End Try
>>
>>
>>
>>
>"Tony M" <TonyMast_NOSPA M@msn.comwrote in message
>news:e$v9PY8yH HA.5980@TK2MSFT NGP04.phx.gbl.. .

>>>
>>>
>>Shouldn't the ExecuteNonQuery be TRUE if it finds a record and FALSE is
>>not?
>>I get FALSE all the time and I seeded the database with the email
>>address.
>>I just want to check if record exist before moving on.
>>If this doesn't work I guess I could load a datatable and check to see
>>if rows 0.
>>>
>>>
>>Dim cnString As OleDbConnection
>>>
>>cnString = New OleDbConnection ("Provider=Micr oSoft.Jet.OLEDB .4.0; Data
>>source = " & Server.MapPath( "Someplace.mdb" ))
>>>
>>Dim CheckCus As New OleDbCommand("S ELECT * from Cus where EMailAddress
>>=" & QM & Trim(txtEMail.T ext) & QM, cnString)
>>>
>>>
>>CheckCus.Conn ection.Open()
>>>
>>If CheckCus.Execut eNonQuery() Then
>> txtFirstName.Te xt = "Yes"
>>Else
>> txtFirstName.Te xt = "No " & Now
>>End If
>>>
>>CheckCus.Conn ection.Close()
>>>
>>Thanks
>>Tony
>>>

>>
>>
>>

>
>

[Scott M.]

Re: ExecuteNonQuery

It's when the user passes data (injects) that would cause SQL to throw an
exception and possibly reveal information about your database, table, fields
away for more detailed attacks. Simply passing a single quote can do it.


"Johnny Jörgensen" <jojo@altcom.se wrote in message
news:%23NlQWloz HHA.4824@TK2MSF TNGP02.phx.gbl. ..

Gotta ask...
>
What the heck is a "SQL injection attack"?
>
Cheers,
Johnny J.
>
>
>
>
"Spam Catcher" <spamhoneypot@r ogers.comwrote in message
news:Xns99781AB 507DABusenethon eypotrogers@127 .0.0.1...

>"Tony M" <TonyMast_NOSPA M@msn.comwrote in
>news:e$v9PY8yH HA.5980@TK2MSFT NGP04.phx.gbl:
>>

>>Dim CheckCus As New OleDbCommand("S ELECT * from Cus where EMailAddress
>>=" & QM & Trim(txtEMail.T ext) & QM, cnString)

>>
>You should always use SQL Parameters for your queries. Otherwise you can
>be
>the victim of a SQL injection attack.

>
>