how to find whether particular value is present in database

[srig]

hi..
i hav created a form which gets empid as input and retrieve data from database and display information about employee.now wen i get empid as input i should check with d table tat empid shold exist. if does not exist i should display a message..
can anyone suggest me d code or idea how can i do it.

[ck9663]

Sounds like an assignment. What do you have so far?

-- CK

[srig]

i hav done for inserting,delet ing,updatin,dis playin..
now i hav to validate

thanks & regards
Sri

[ck9663]

Could you post what you have so far?

-- CK

[srig]

how to find whether particular value is present in database

i hav created forms for insertin emp detail,deletin, updatin and viewing..wen i insert i need to check whether the id i am giving exist already in a database or not.. if exist i should display an error mess..
u need the code of front end wat i hav done or the database..im sorry i don get u whether i should post my entire code or not.

thanks
sri

[ck9663]

Use Search Condition


-- CK

[OuTCasT]

Private Function ValidateEmployeeID(ByVal EmployeeCode As String) As Boolean
        Dim sqlCon As SqlConnection = Nothing
        Dim sqlCom As SqlCommand = Nothing
        Dim lookupID As String

        lookupID = Nothing

        'Check for EmployeeCode
        If ((EmployeeCode Is Nothing)) Then
            MsgBox("[ValidateEmployeeID] Input Validation of EmployeeID Failed", MsgBoxStyle.Critical)
            Return False
        End If
        Try
            sqlCon = New SqlConnection("Data Source=./SQLEXPRESS;Initial Catalog=<DBNAME>;Integrated Security=True")
            sqlCon.Open()

            'Create sqlCommand to retrieve EmployeeId
            sqlCom = New SqlCommand("select [employeeId] from EmployeeDetails where [employeeid]=@EmployeeID COLLATE SQL_Latin1_General_CP1_CI_AS", sqlCon)
            sqlCom.Parameters.Add("@EmployeeID", SqlDbType.VarChar, 25)
            sqlCom.Parameters("@EmployeeID").Value = txtEmployeeCode.Text

            lookupID = sqlCom.ExecuteScalar

            sqlCom.Dispose()
            sqlCon.Dispose()
        Catch ex As Exception
            sqlCom.Dispose()
            sqlCon.Dispose()
            MsgBox("Employee ID Already Exists Please make another selection", MsgBoxStyle.Information)
        End Try
        If (lookupID Is Nothing) Then
            Return False
        End If
        Return (String.Compare(lookupID.ToUpper, txtEmployeeCode.Text.ToUpper, False) = 0)
    End Function

[Gradwohl]

your problem

' will not work
' If ((EmployeeCode Is Nothing)) Then
' MsgBox("[ValidateEmploye eID] Input Validation of EmployeeID Failed", MsgBoxStyle.Cri tical)
' Return False
' End If
' this will fire!
If IsNull(Employee Code) Then
MsgBox("[ValidateEmploye eID] Input Validation of EmployeeID Failed", MsgBoxStyle.Cri tical)
Return False
End If

[OuTCasT]

' will not work
' If ((EmployeeCode Is Nothing)) Then
' MsgBox("[ValidateEmploye eID] Input Validation of EmployeeID Failed", MsgBoxStyle.Cri tical)
' Return False
' End If
' this will fire!
If IsNull(Employee Code) Then
MsgBox("[ValidateEmploye eID] Input Validation of EmployeeID Failed", MsgBoxStyle.Cri tical)
Return False
End If

This is not really needed actually.