SQL 两个无关的查询结果如何合并成多列

Question

表1字段A、B、C；表2字段D、E、F；
如何根据表1和表2信息，生成表3信息。

Answer 1

 select a.*, b.* from (select ROW_NUMBER() over(order by A) as id, * from table1) a
left join (select ROW_NUMBER() over(order by D) as id, * from table2) b on a.id = b.id

Answer 2

Answer 3

select * from table1
left join table2 on 1=1

Answer 4

Answer 5

完整C#代码

 using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace Q692230
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            SqlConnection conn = new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=\"C:\\Documents and Settings\\user1\\My Documents\\Q692230DB.mdf\";Integrated Security=True;Connect Timeout=30;User Instance=True");
            conn.Open();
            string sql =
@"select a.A, a.B, a.C, b.D, b.E, b.F from (select ROW_NUMBER() over(order by A) as id, * from table1) a
left join (select ROW_NUMBER() over(order by D) as id, * from table2) b on a.id = b.id";
            SqlCommand cmd = new SqlCommand(sql, conn);
            DataSet ds = new DataSet();
            SqlDataAdapter ad = new SqlDataAdapter(cmd);
            ad.Fill(ds);
            dataGridView1.DataSource = ds.Tables[0];
        }
    }
}

Answer 6

mysql亲测可用, 其中 order by ... limit 10, 可以去掉不用的。

select X.A, X.B, X.C, Y.D, Y.E, Y.F from
(Select (@rowNum:=@rowNum+1) as rowNo, A, B, C
From t1, (Select (@rowNum :=0) ) x1
Order by t1.id desc limit 10) X
left join
(Select (@rowNum2:=@rowNum2+1) as rowNo, D, E, F
From t2,
(Select (@rowNum2 :=0) ) y1
Order by t2.id desc limit 10) Y
on X.rowNo = Y.rowNo;

Answer 7

稍微修改下

 select a.A, a.B, a.C, b.D, b.E, b.F from (select ROW_NUMBER() over(order by A) as id, * from table1) a
left join (select ROW_NUMBER() over(order by D) as id, * from table2) b on a.id = b.id"