System.Data.SqlClient.SqlException：'，'附近的语法不正确。 C＃

Question

I'm new to StackOverflow and , so sorry in advance if I am not explaining things correctly. i want to delete row from DoctorTbl but i get this message:

'Incorrect syntax near ','.'

can someone help me please??

---

    SqlDataAdapter DoctorAdapter;
    DataTable Doctordt;

    public DalDoctor()
    {
        DoctorAdapter = new SqlDataAdapter();
        PreperCommands();
    }
    public DalDoctor(string conn) : base(conn)
    {
        DoctorAdapter = new SqlDataAdapter();
        PreperCommands();
    }
    private void PreperCommands()
    {   //select command
        DoctorAdapter.SelectCommand = Conn.CreateCommand();
        DoctorAdapter.SelectCommand.CommandText = "SELECT * FROM DoctorTbl";
        //delete command
        DoctorAdapter.DeleteCommand = Conn.CreateCommand();
        DoctorAdapter.DeleteCommand.CommandText = "DELETE FROM DoctorTbl WHERE DocFirstName=@DocFirstName,DocLastName=@DocLastName,ExpertiseId=@ExpertiseId,License=@License,DocTelephone=@DocTelephone,DoctorId=@DoctorId";
        DoctorAdapter.DeleteCommand.Parameters.Add("@DocFirstName", SqlDbType.NChar, 10, "DocFirstName");
        DoctorAdapter.DeleteCommand.Parameters.Add("@DocLastName", SqlDbType.NChar, 10, "DocLastName");
        DoctorAdapter.DeleteCommand.Parameters.Add("@ExpertiseId", SqlDbType.Int, 10, "ExpertiseId");
        DoctorAdapter.DeleteCommand.Parameters.Add("@License", SqlDbType.Int, 10, "License");
        DoctorAdapter.DeleteCommand.Parameters.Add("@DocTelephone", SqlDbType.Int, 10, "DocTelephone");
        DoctorAdapter.DeleteCommand.Parameters.Add("@DoctorId", SqlDbType.Int, 10, "DoctorId");
    }
    public bool SaveToDB(DataTable dt)
    {
        //try
        //{
            DoctorAdapter.Update(dt);
            return true;
        //}
        //catch (SqlException ex)
        //{
        //    return false;
        //}

    }

    public DataTable FillTable()
    {
        DataTable dt = new DataTable();
        DoctorAdapter.Fill(dt);
        dt.TableName = "DoctorTbl";
        return dt;
    }
    public bool delete(DataRow rowdelete)
   {     

        Doctordt = FillTable();
        foreach (DataRow dr in Doctordt.Rows)
        {
            if (Convert.ToInt32(dr["DoctorId"]) == Convert.ToInt32(rowdelete["DoctorId"]))
            {
                dr.Delete();
            }
        }
        return SaveToDB(Doctordt);

    }

here i get the eror:(in this order : DoctorAdapter.Update(dt);)

---

    public bool SaveToDB(DataTable dt)
    {
        try
        {
            DoctorAdapter.Update(dt);
            return true;
        }
        catch (SqlException ex)
        {
            return false;

        }

    }

Answer 1

Well, you can't specify conditions on multiple columns using , comma operator. It has to be either a AND or OR condition. That's the exact error you are getting.

WHERE DocFirstName=@DocFirstName,DocLastName=@DocLastName,ExpertiseId=@ExpertiseId,...

should be

WHERE DocFirstName=@DocFirstName
AND DocLastName=@DocLastName
AND ExpertiseId=@ExpertiseId
AND License=@License
.......

Answer 2

Your error is caused by an incorrect syntax in the WHERE clause. Here every condition should be linked to the next with an AND or OR statement.

However, to delete a record from a table you simply need to know the Primary Key of that table and use a value from your data to search that single record in the database. Also there is no need to use an SqlDataAdapter in your scenario to delete a row

So assuming that DoctorID is the primary key, you could delete the database record with....

public bool delete(DataRow rowdelete)
{     
    using(SqlCommand cmd = conn.CreateCommand())
    {
        cmd.CommandText = "DELETE FROM DoctorTbl WHERE DoctorID = @doctorid";
        cmd.Parameters.Add("@doctorid", SqlDbType.Int).Value = Convert.ToInt32(rowdelete["DoctorId"]);
        cmd.ExecuteNonQuery();

        // Now fix the in memory table to remove the deleted row 
        DataTable dt = rowDelete.Table;
        rowDelete.Delete();
        table.AcceptChanges();
    }
}