1、查詢某個日期接下來的幾天:
select '2016-02-0'::date + i;
2、確定某個表是否存在:
SELECT COUNT(*) FROM pg_class WHERE relname = ‘表名’
3、做除數時需要的判斷:
case when sum(count)=0 hen 0 else sum(h.speed * h.count)/sum(h.count) end as speed
4、執行存儲過程:
SELECT COUNT(1) FROM 存儲過程名稱
5、一段時間內:
WHERE stat_time Between ‘2016-01-01’ AND ‘2016-05-01’
6、把某個時間按月來統計
SELECT to_char(stat_time,'yyyy-mm') as months