Some Doubt in retrieving PaRTIUCLAR pROJECT iD

Question

I DESIGN A small application as follows;

Project ID          Combobox1
Project Name      Textbox1
Rate                  Textbox2
Unit                   Textbox3
Amt                   Textbox4

all the datas are stored in the database.

I have one textbox and one button(button name Project Wise Id)in textbox i type the letter R Only the project id start with R want to display the output as follows;

Project ID    Project Name  Rate  Unit  Amt    
R001            Embedded      30     16      480
R002            Embedded      40     16      640
                                                         1120 

Project ID    Project Name  Rate  Unit  Amt    
P001            JAva              15      5       75
P002            .Net              20     10      200
R001            Embedded      30     16      480
R002            Embedded      40     16      640
                     Total                            1395
            

private void button3_Click(object sender, EventArgs e)
        {
            con = new SqlConnection("Server=(local);initial catalog=master;Trusted_Connection=True");
            con.Open();
            string str = "select * from Project where PojectID like = '" + cb_id.SelectedItem + "'";
            SqlCommand com = new SqlCommand(str, con);
            SqlDataAdapter sqlda = new SqlDataAdapter(com);
            DataSet ds = new DataSet();
            sqlda.Fill(ds, "Project");
            con.Close();

            ReportDocument r1 = new ReportDocument();
            //r1.Load("Full Path of Your Report\Employee.rpt");
            //string path = Server.MapPath("Reports/Service Bill.rpt");
            r1.Load("Reports/ProjectReport.rpt");
            r1.SetDataSource(ds);
            crystalReportViewer1.ReportSource = r1;
            crystalReportViewer1.RefreshReport();
 }

Here this query is Correct  "select * from Project where PojectID like = '" + cb_id.SelectedItem + "'";

From the above please correct the query i have some doubt.