SQL查询-在UNION中使用Order By

Question

从两个表中提取数据时，如何以编程方式对联合查询进行排序？例如，

SELECT table1.field1 FROM table1 ORDER BY table1.field1

UNION

SELECT table2.field1 FROM table2 ORDER BY table2.field1

引发异常

注意：正在MS Access Jet数据库引擎上尝试这样做

Answer 1

有时您需要ORDER BY在每个部分中将与组合在一起UNION。在这种情况下SELECT * FROM (  SELECT table1.field1 FROM table1 ORDER BY table1.field1) DUMMY_ALIAS1UNION ALLSELECT * FROM(   SELECT table2.field1 FROM table2 ORDER BY table2.field1) DUMMY_ALIAS2

Answer 2

SELECT field1 FROM table1UNIONSELECT field1 FROM table2ORDER BY field1