[转自]
http://www.itpub.net/thread-1355835-1-1.html
any和some是等价的,其与all的前面都只能是比较符号,即=, !=, >, <, <=, >=;其与all的后面都只能是子查询或者一串值
any的含义是将一个值与any后的每一个值去比较,满足任何一个比较条件即为true
all的含义是将一个值与all后的每一个值去比较,满足全部比较条件才为true
CREATE TABLE tmp_test(ID number,txt VARCHAR2(10)); CREATE table tmp_test_his AS SELECT * from tmp_test WHERE 1=2; INSERT INTO tmp_test VALUES(1,'a'); INSERT INTO tmp_test VALUES(2,'b'); INSERT INTO tmp_test VALUES(3,'c'); INSERT INTO tmp_test VALUES(4,'d'); INSERT into tmp_test_his VALUES(2,'b'); INSERT into tmp_test_his VALUES(3,'c'); INSERT into tmp_test_his VALUES(4,'x');
select a.* FROM tmp_test_his a where (a.id,a.txt) = all(select b.id,b.txt from tmp_test b where a.id=b.id and a.txt=b.txt); ID TXT ---------- ---------- 2 b 3 c 4 x 3 rows selected.
select b.id,b.txt from tmp_test b,tmp_test_his a where a.id=b.id and a.txt=b.txt; ID TXT ---------- ---------- 2 b 3 c 2 rows selected.
select a.* FROM tmp_test_his a where (a.id,a.txt) = all(select b.id,b.txt from tmp_test b, tmp_test_his a where a.id=b.id and a.txt=b.txt); no rows selected.
select a.* FROM tmp_test_his a where (a.id,a.txt) = any(select b.id,b.txt from tmp_test b, tmp_test_his a where a.id=b.id and a.txt=b.txt); ID TXT ---------- ---------- 2 b 3 c 2 rows selected.