Getting selected values from the table into another table based on a condition

string conStr,sqlQuery;
int sal;
SqlConnection con = new SqlConnection(conStr);
SqlCommand cmd = new SqlCommand();
SqlDataAdapter da = null;
DataTable dt = new DataTable();
con.Open();
cmd.Connection = con;

//make data for testing  #saltable for salaries and #salhike to store salary hikes
sqlQuery = "create table #saltable(empid varchar(5),empname varchar(10),jan11 int,feb11 int,mar11 int)";
cmd.CommandText = sqlQuery;
cmd.ExecuteNonQuery();
sqlQuery = "create table #salhike(empid varchar(5),hike int,date varchar(10))";
cmd.CommandText = sqlQuery;
cmd.ExecuteNonQuery();
sqlQuery = "insert into #saltable select '12','ram',10,10,20";
cmd.CommandText = sqlQuery;
cmd.ExecuteNonQuery();

sqlQuery = "SELECT empid,empname,jan11,feb11,mar11 from #salTable where empid='"+ txtItem.Text +"'";
da = new SqlDataAdapter(sqlQuery, con);
da.Fill(dt);
sal = Convert.ToInt32(dt.Rows[0][2].ToString());
for (int i = 0; i < dt.Rows.Count; i++)
    for (int j = 2; j < dt.Columns.Count; j++) //from third column to last            {
        //if there is hike in salary
        if (sal < Convert.ToInt32(dt.Rows[i][j].ToString()))
        {
            string hike = Convert.ToString(Convert.ToInt32(dt.Rows[i][j].ToString()) - sal);
            sal = Convert.ToInt32(dt.Rows[i][j].ToString());   //set this as new base value
            //insert difference in a table
            sqlQuery = "INSERT into #salHike(empid,hike,date)";
            sqlQuery += " SELECT '"+ txtItem.Text +"',"+ hike +",'"+ dt.Columns[j].ColumnName +"'";
            cmd.CommandText = sqlQuery;
            cmd.ExecuteNonQuery();
        }
    }
dt = new DataTable();

sqlQuery = "SELECT * from #salHike";
da = new SqlDataAdapter(sqlQuery, con);
da.Fill(dt);
GridView1.DataSource = dt;
GridView1.DataBind();
con.Close();