Inner Join two tables and getting their values

here is the code
I'm getting the field names in the DataGridView but not the values

Code:

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_string = "select Employer.CompanyName,Employee.Firstname from Employee inner join Employer on Employee.IDEmployer = Employer.EmployerID"

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here is the screenshot.
Attachment 96579

Obviously that's not all the relevant code so you might show us the rest. Presumably you are calling Fill on a data adapter. The first step is to check the value returned by that. If it's zero then that means that there are no rows that match your query criteria. If it's not zero then there's some issue with your binding.

Here is the full code

Code:

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Public Function DGVload_testsql() As DataView
        Dim con = New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Users\Danial\documents\visual studio 2010\Projects\ESI_PF_Payroll_V1\ESI_PF_Payroll_V1\Pay.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True")
        con.Open()
        '_string = "select * from Employee inner join Employer on Employee.IDEmployer = Employer.EmployerID"
        _string = "select Employer.CompanyName,Employee.Firstname from Employee inner join Employer on Employee.IDEmployer = Employer.EmployerID"
        Dim SampleSource As New DataSet
        Dim TableView As DataView
        Try
            Dim SampleCommand As New SqlCommand()
            Dim SampleDataAdapter = New SqlDataAdapter()
            SampleCommand.CommandText = _string
            SampleCommand.Connection = con
            SampleDataAdapter.SelectCommand = SampleCommand
            SampleDataAdapter.Fill(SampleSource)
            TableView = SampleSource.Tables(0).DefaultView
            'Use colors in DataGridView
            Test_dgv_sql.GridColor = Color.Red
            Test_dgv_sql.CellBorderStyle = DataGridViewCellBorderStyle.None
            Test_dgv_sql.BackgroundColor = Color.LightGray

            Test_dgv_sql.DefaultCellStyle.SelectionBackColor = Color.Brown
            'DGV1.DefaultCellStyle.SelectionForeColor = Color.Yellow

            Test_dgv_sql.DefaultCellStyle.WrapMode = DataGridViewTriState.[True]

            Test_dgv_sql.SelectionMode = DataGridViewSelectionMode.FullRowSelect
            Test_dgv_sql.AllowUserToResizeColumns = False

            Test_dgv_sql.RowsDefaultCellStyle.BackColor = Color.Bisque
            Test_dgv_sql.AlternatingRowsDefaultCellStyle.BackColor = Color.Beige

            Test_dgv_sql.ColumnHeadersDefaultCellStyle.BackColor = Color.DarkRed
            Test_dgv_sql.ColumnHeadersDefaultCellStyle.ForeColor = Color.DarkGray

            'cells and rows height in DataGridView
            Dim row As DataGridViewRow = Me.Test_dgv_sql.RowTemplate
            row.DefaultCellStyle.BackColor = Color.Bisque
            row.Height = 30
            row.MinimumHeight = 15

        Catch ex As Exception
            Throw
        End Try
        Return TableView
    End Function
End Class

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Code:

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Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
     
        Test_dgv_sql.DataSource = DGVload_testsql()
     
    End Sub

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Are you sure there are matching records in the db?

Yes both the tables have there first name matching,with column name Firstname
Employer table,Fieldname Firstname = Danial
Employee table,Fieldname Firstname = Danial

Maybe you could read all of my post instead of just the first sentence.

Quote:

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Originally Posted by jmcilhinney

Presumably you are calling Fill on a data adapter. The first step is to check the value returned by that. If it's zero then that means that there are no rows that match your query criteria. If it's not zero then there's some issue with your binding.

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Try to break down your problems into simple steps, verifying along the way what works and what doesn't, then you'll find where the problem lies.
In this case, try a simple sql query and see if that works, before worrying about the join.
Once the fill works, then you can worry about the SQL.

And it's easier to play with SQL in Management Studio first, IMHO

(dupe - can't delete)
(technical error made me re-post the posting, and surprise surprise it had already posted despite a "database error")

I have assigned fk to EmpoyerID on the employee table and then the data is there ,but now I wonder weather now the two tables related or not ,If I create employer profile and add three employee how do I know they are related to the employer?

It should not allow you to enter and employer id in the employee table which is not in the employer table already.