SQL查询中"<"附近的语法不正确

Question

       String start_cd;
       String end_cd;
       int time_start_int;
       int time_end_int;
        opencon();

        SqlCommand res = new SqlCommand("SELECT ID,Available,Type," + start_cd + "," + 
            end_cd + " FROM " + going + 
           " WHERE " + start_cd + "!=0 or " + end_cd + "!=0 and " + 
           time_start_int + " <= " + start_cd + " <= " + time_end_int + "", con);
        SqlDataAdapter sda_res = new SqlDataAdapter(res);
        DataTable dt_res = new DataTable();
        sda_res.Fill(dt_res);

        listBox1.DataSource=dt_res;
        listBox1.DisplayMember="ID";

        listBox2.DataSource = dt_res;
        listBox2.DisplayMember = start_cd;

我想获取sql表time_start_int之间的列值time_end_int

我收到了错误

'<'附近的语法不正确.

Answer 1

您无法start <= column <= end在SQL查询中编写.

你需要这样做:

"...and start_cd >= " + time_start_int + " and " + start_cd + " <= " + time_end_int

但请不要连接你的字符串,这使你容易受到SQL注入.使用SQL参数.