informix如何查询第一条记录

1.select first 1 * from shop;正序查询第一条数据

2.select first 1 * from shop order by create_time desc;按创建时间倒序查询第一条数据

3.select first 1 shopid from shop;正序查询第一条数据中的shopid字段

4.select first 1 shopid from shop order by create_time desc;按创建时间倒序查询第一条数据的shopid字段