各資料庫取資料的前N條記錄
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
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