Question

i should say hi experts 😀 . Help me with this pretty code 🙂

The database:

“ID (Primary key)” | “Title”
0 | “title1”
1 | “title2”
2 | “title3”
3 | “title4”

---

Sub AddRecord(ByVal Table As String, ByVal Columns As String, ByVal Record() As String)
    Dim SubDir As String = ""

    Dim Adapter As OleDbDataAdapter = New OleDbDataAdapter("SELECT * FROM " & Table, connectionString)
    Dim command As OleDbCommand
    Dim tbCorrectSyntax = ""

    Using connection As New OleDbConnection(connectionString)
        Try
            connection.Open()
            Dim Commandtxt As String = ""
            For i = 0 To Record.GetUpperBound(0)
                If Record(i).IndexOf(",") > 0 Then
                    Dim tmpRec() As String = Nothing
                    Dim cols() As String = Nothing

                    tmpRec = Record(i).Split(",")
                    cols = Columns.Split(",")

                    For j = 0 To tmpRec.GetUpperBound(0)
                        tbCorrectSyntax &= cols(j) & " = '" & tmpRec(j) & "' " & IIf(j = tmpRec.GetUpperBound(0), "", " , ")
                    Next
                End If


                Dim txtCorrect As String = IIf(tbCorrectSyntax = "", Columns & " = " & Record(i), tbCorrectSyntax)

                Commandtxt = "IF OBJECT_ID ( 'InsertOrUpdateItem', 'P' ) IS NOT NULL " & _
                                "DROP PROCEDURE InsertOrUpdateItem " & _
                             "GO " & _
                             "CREATE PROCEDURE InsertOrUpdateItem " & _
                                "AS " & _
                                "IF (EXISTS (SELECT * FROM " & Table & _
                                            " WHERE " & txtCorrect & "))" & _
                                            " begin " & _
                                                "UPDATE (" & Table & ") " & _
                                                txtCorrect & _
                                                " WHERE " & txtCorrect & " " & _
                                            " End " & _
                                            " else " & _
                                                " begin " & _
                                                " INSERT INTO " & Table & " (" & Columns & ") " & _
                                                " VALUES (" & Record(i) & ")" & _
                                            " End " & _
                                "End "

                'Commandtxt = "INSERT INTO " & Table & " (" & Columns & ") VALUES (" & Record(i) & ")"
                command = New OleDbCommand(Commandtxt, connection)
                command.CommandType = CommandType.StoredProcedure
                command.ExecuteNonQuery()

            Next


        Catch ex As Exception
            msgbox(ex.Message)
        Finally
            connection.Close()
        End Try
    End Using
End Sub

Function connectionString() As String
    Return "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & DBdir & ";User Id=admin;Password=;"
End Function

---

The first procedure is a wrapper to add data to database fields (if the data doent exist)
But update it the row with new data already exist.

Input:
Table = TableName
Columns = name of colomns that will be updated separated by comma (Ex1: “ID” , Ex2: “ID,Title,…”)
Record() = string array that represent the new values( multiple values are separated with comma)

OK, before adding values to database, we should check if a row exists with this values 🙂
TO do this, creating a Stored Procedure is a best way to deal with the database fastly.

So… The problem now is, at the runtime, Miss OleDB throw this error:
Microsoft Jet database engine cannot find the input table or query ‘IF’ ….

Thanks in advance 😀

Answer 1

I found a solution for my problem (with a little net research 🙂 ) hahahaha i m happy
anyway, the initial question was: ‘How to update a record in database if it exists’
So i tryed to create and store a Stored procedure in the database… but… 🙂

Then i found an interesting Method: the ExecuteScalar of OleDBcommand Class

It simply return a value according to Sql input : in the following example that i used, it return the index (primary key) if the recod exists. So lets begin:

Function GetRecordIndex(ByVal Table As String, ByVal Columns As String, ByVal Record As String) As String
    Dim Commandtxt As String = ""
    Dim Command As OleDbCommand
    Dim tbCorrectSyntax As String = ""
    Dim tbCorrectSyntaxAND As String = ""

    Using connection As New OleDbConnection(connectionString)

        Try
            connection.Open()
            If Record.IndexOf(",") > 0 Then
                Dim tmpRec() As String = Nothing
                Dim cols() As String = Nothing

                tmpRec = Record.Split(",")
                cols = Columns.Split(",")

                For j = 0 To tmpRec.GetUpperBound(0)
                    tbCorrectSyntax &= cols(j) & "='" & tmpRec(j) & "' " & IIf(j = tmpRec.GetUpperBound(0), "", " , ")
                    tbCorrectSyntaxAND &= cols(j) & "='" & tmpRec(j) & "' " & IIf(j = tmpRec.GetUpperBound(0), "", " AND ")
                Next
            End If
            Dim txtCorrect As String = IIf(tbCorrectSyntax = "", Columns & "=" & Record, tbCorrectSyntax)
            Dim txtCorrectAND As String = IIf(tbCorrectSyntaxAND = "", Columns & "=" & Record, tbCorrectSyntaxAND)

            Commandtxt = "SELECT * FROM " & Table & " WHERE " & txtCorrectAND
            Command = New OleDbCommand(Commandtxt, connection)
            Dim RecordIndex As String = Command.ExecuteScalar

            Return RecordIndex

        Catch ex As Exception
            Return Nothing
        Finally
            connection.Close()
        End Try
    End Using
End Function

As before, Columns Parameter can be a single Database column, or multiple columns separated with comma . same thing with Record that represent the data inside each column

Thank for your help
Fadelovesky