Sql UNION 合并多个结果集并排序

1.建表语句及测试数据：

--创建表A
CREATE TABLE A(
	A1 int NULL,
	A2 nvArchAr(50) NULL,
	A3 decimAl(18, 0) NULL
) 
--测试数据
INSERT INTO A VALUES (1,'A1',1)
INSERT INTO A VALUES (2,'A2',1)
INSERT INTO A VALUES (3,'A3',1) 

--创建表B
CREATE TABLE B(
	B1 int NULL,
	B2 nvArchAr(50) NULL,
	B3 decimAl(18, 0) NULL
) 
--测试数据
INSERT INTO B VALUES (1,'B1',1)
INSERT INTO B VALUES (2,'B2',1)
INSERT INTO B VALUES (3,'B3',1)
INSERT INTO B VALUES (4,'B4',1)
INSERT INTO B VALUES (5,'B5',1)

2.数据预览：

A表：

B表：

3.合并数据集：

SELECT ROW_NUMBER() OVER(ORDER BY a) ROW_NUM,
       *
FROM   (
	       --结果集1
           (
               SELECT A1 AS a,
                      A2 AS b,
                      A3 AS c
               FROM   A
           )
           UNION
           --结果集2
           (
               SELECT B1 AS a,
                      B2 AS b,
                      B3 AS c
               FROM   B
           )
       )temp