查询数据限制显示条数
1. ORACLE
   SELECT * FROM TABLE1 WHERE ROWNUM<=N
   HQL: from table1 t order by t.createTime desc 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
   GO
   SELECT * FROM TABLE1
6. MYSQL
   SELECT * FROM TABLE1 LIMIT N
   hibernate查询记录的前10条记录
   就像mysql的SQL语句的"select * from table limit 10" hql 不支持limit
   query.setFirstResult(0);//从第0条开始取
   query.setMaxResults(10);//取十条记录
7. FOXPRO
   SELECT * TOP N FROM TABLE ORDER BY COLUMN
8. postgres查询前几条记录SQL
   SELECT * FROM TABLE LIMIT