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Problem in SQL statement in VB.NET.. Assistance Required.
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Join Date: Jun 2008
Posts: 117
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Junior Poster
Can you please tell me what's wrong with this statement ? i get no errors but I get no o/p either!
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Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
Dim con As OleDbConnection = New OleDb.OleDbConnection("provider=microsoft.jet.oledb.4.0;data source=C:\Documents and Settings\bashkark\Desktop\Copy of USERS.mdb")
If (ComboBox6.SelectedItem = 0.5) And (ComboBox7.SelectedItem) Then
Dim cmd1 As New OleDbCommand
cmd1 = New OleDbCommand("select * from table1 where RAM between 0.5000 and 2.000")
End If
End Sub
Hi,
You specified the connection and command objects but you probably want a data reader...also you'll need to open the connection.
You specified the connection and command objects but you probably want a data reader...also you'll need to open the connection.
VB.NET Syntax (Toggle Plain Text)
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Join Date: Jun 2008
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Junior Poster
Hi Ripper thanks for ur reply..
the error that i get is
"Conversion from string "" to type 'Double' is not valid." at the line
"If (ComboBox6.SelectedItem = "") And (ComboBox7.SelectedItem = "") Then"
please help me rectify this problem!!
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KB - Knowledge is Power!
QUOTE=RipperJT;652629]Hi,
You specified the connection and command objects but you probably want a data reader...also you'll need to open the connection.
[/QUOTE]
the error that i get is
"Conversion from string "" to type 'Double' is not valid." at the line
"If (ComboBox6.SelectedItem = "") And (ComboBox7.SelectedItem = "") Then"
please help me rectify this problem!!
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Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
Dim con As OleDbConnection = New OleDb.OleDbConnection("provider=microsoft.jet.oledb.4.0;data source=C:\Documents and Settings\bashkark\Desktop\Copy of USERS.mdb")
Dim cmd1 As New OleDbCommand
If (ComboBox6.SelectedItem = "") And (ComboBox7.SelectedItem = "") Then
MsgBox("No Values have been entered ! ")
End If
cmd1 = New OleDbCommand("select * from table1 where RAM between '%" & ComboBox6.SelectedItem & "%' and '%" & ComboBox7.SelectedItem & "%'", con)
End Sub
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KB - Knowledge is Power!
QUOTE=RipperJT;652629]Hi,
You specified the connection and command objects but you probably want a data reader...also you'll need to open the connection.
VB.NET Syntax (Toggle Plain Text)
It's trying to convert the datatype on the left side to the empty string on the right side of the =. Try...
VB.NET Syntax (Toggle Plain Text)
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Join Date: Jun 2008
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Junior Poster
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Originally Posted by RipperJT 
It's trying to convert the datatype on the left side to the empty string on the right side of the =. Try...
VB.NET Syntax (Toggle Plain Text)
just curious..what does that statement do ?
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Join Date: Jun 2008
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Junior Poster
I get the error in the "if" statement. please take a look at it..
if i hit the "click" button directly without choosing the RAM values I expect the Msg box to pop up ..instead i get an error.. ! pls see code for error../
if i hit the "click" button directly without choosing the RAM values I expect the Msg box to pop up ..instead i get an error.. ! pls see code for error../
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Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
Dim con As OleDbConnection = New OleDb.OleDbConnection("provider=microsoft.jet.oledb.4.0;data source=C:\Documents and Settings\bashkark\Desktop\Copy of USERS.mdb")
Dim cmd1 As New OleDbCommand
If (ComboBox6.SelectedItem = " ") And (ComboBox7.SelectedItem = " ") Then //error:"conversion from string"" to 'double' is not valid"
MsgBox("No Values have been entered !")
End If
cmd1 = New OleDbCommand("select * from table1 where RAM between '& ComboBox6.SelectedItem & ' and '& ComboBox7.SelectedItem & '", con)
Dim da As OleDbDataAdapter = New OleDbDataAdapter(cmd1)
Try
Dim ds As DataSet = New DataSet()
da.Fill(ds, "table1") //error : data type mismatch in criteria expression
DataGridView1.DataSource = ds.Tables("table1").DefaultView
Finally
con.Close()
cmd1 = Nothing
da.Dispose()
con.Dispose()
End Try
End Sub
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Join Date: Jun 2008
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Junior Poster
Data type mismatch in criteria expression.is the error that i get at line da.Fill(ds, "table1") if i modified the code as below (after removing the"if" statement"
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Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
Dim con As OleDbConnection = New OleDb.OleDbConnection("provider=microsoft.jet.oledb.4.0;data source=C:\Documents and Settings\bashkark\Desktop\Copy of USERS.mdb")
Dim cmd1 As New OleDbCommand
cmd1 = New OleDbCommand("select * from table1 where RAM between '& ComboBox6.SelectedItem & ' and '& ComboBox7.SelectedItem & '", con)
Dim da As OleDbDataAdapter = New OleDbDataAdapter(cmd1)
Try
Dim ds As DataSet = New DataSet()
da.Fill(ds, "table1")
DataGridView1.DataSource = ds.Tables("table1").DefaultView
Finally
con.Close()
cmd1 = Nothing
da.Dispose()
con.Dispose()
End Try
End Sub
Do you have real values selected in the combobox6 & 7 when the click event is fired or does it only fail when you haven't specified any values? If there isn't any values select then you should not run the query.
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Join Date: Jun 2008
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Junior Poster
hi ripper..either way i get the same error on da.fill(ds,"table1"). that is..when i dont choose any value from either combobox and hit the click and when i choose 1 value from each of the 2 combo boxes and hit click..
yesboth my combo boxes have numbers like.2.980, 3.000,0.5000,3.000,1.000,2.000,3.250 in each of them..
pls suggest something..i have been stuck on this for weeks now..
yesboth my combo boxes have numbers like.2.980, 3.000,0.5000,3.000,1.000,2.000,3.250 in each of them..
pls suggest something..i have been stuck on this for weeks now..
You can try to test to see if a value has been entered and if so then run your code.
Here's info an the function IsNumeric
http://msdn.microsoft.com/en-us/libr...w1(VS.71).aspx
VB.NET Syntax (Toggle Plain Text)
Here's info an the function IsNumeric
http://msdn.microsoft.com/en-us/libr...w1(VS.71).aspx
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