oracle rownum的使用
选择表中的某一行记录:(理解:rownum是oracle系统顺序分配为从查询返回的行的编号)
select * from (select rownum a,t.* from testtab t) where a=2;
select * from (select rownum a,t.* from testtab t) where a=3;
select * from (select rownum a,t.* from testtab t) where a=4;
不能为:
select * from (select rownum,t.* from testtab t) where rownum=2;或
select * from testtab where rownum=2;
返回多行记录:
select * from testtab where rownum<=10;
......
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