查询表中前几行数据

查询数据表的前几行数据:

Oracle:
select * from TableName  where  rownum<=N

SQL Server:
select top N * from TableName

DB2:
select * from TableName fetch first N rows only

My SQL:
select * from TableName limit N

INFORMIX:
select first N * from TableName

注:N为需要显示的行数