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不同DB取前几条记要汇总

发布时间: 2012-08-09 15:59:21 作者: rapoo

不同DB取前几条记录汇总
介绍取一表前N条记录的各种数据库的写法...
1. ORACLE
SELECT * FROM TABLE1 WHERE ROWNUM<=N
2. INFORMIX
SELECT FIRST N * FROM TABLE1
3. DB2
SELECT * ROW_NUMBER() OVER(ORDER BY COL1 DESC) AS ROWNUM WHERE ROWNUM<=N
DB2
SELECT COLUMN FROM TABLE FETCH FIRST N ROWS ONLY
4. SQL SERVER
SELECT TOP N * FROM TABLE1
5. SYBASE
SELECT TOP N * FROM TABLE1
6. mysql:
select * from table_name limit N


1):select * from fromname where rownum<=10
2):如果需要排序,在8i中是
select * from (select * from table order by ……) where rownum<10
3):select 字段1,字段2 from (select * from infotb order by infoid desc) where rownum<=5
子查询内没有的字段,外查询就不能查这个字段.

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