查询前几条记录SQL在不同数据库中的用法
1. ORACLE
SELECT * FROM TABLE1 WHERE ROWNUM<=N
2. INFORMIX
SELECT FIRST N * FROM TABLE1
3. DB2
SELECT * FROM (SELECT T.*, ROW_NUMBER() OVER(ORDER BY COL1 DESC) AS ROWNUM FROM T) AS T WHERE ROWNUM<=N
或者
SELECT COLUMN FROM TABLE FETCH FIRST N ROWS ONLY
4. SQL SERVER
SELECT TOP N * FROM TABLE1
5. SYBASE
SET ROWCOUNT N GOSELECT * FROM TABLE1
6. MYSQL
SELECT * FROM TABLE1 LIMIT N
7. FOXPRO
SELECT * TOP N FROM TABLE ORDER BY COLUMN
不过个人认为oracle的rownum查询不太好，喜欢使用rank函数进行排序和部分记录的选择（好比前几条，中间几条）。