mySql 學習總結

今天基本完成了專案的模組的基本功能，剩下的就是對專案的吃透，對各種工具類的掌握，其中sql語句的書寫就顯得很重要了，特別是新的任務就是   寫乙個統計板塊，sql語句基本從網上各大扒，基本已經成型，上沒有完成的是對sql語句執行完之後得到的資料的封裝並且**給前端

現總結今天的sql函式

select sum(case when  sys_user.uname ='超級管理員' then 1 else 0 end) ,

sum(case when biz_order.uid = '21' then 1 else 0 end) ,
sum(case when biz_order.uid = 'qiuzhilinceshi' then 1 else 0 end) 
from biz_order
left join sys_user on sys_user.uid = biz_order.uid
where year(biz_order.oacceptancedate)between '2017' and '2018'; 
group by biz_order.uid

select   

sum(case month(biz_order.oacceptancedate) when '1' then 1 else 0 end) as january, 
sum(case month(biz_order.oacceptancedate) when '2' then 1 else 0 end) as february, 
sum(case month(biz_order.oacceptancedate) when '3' then 1 else 0 end) as march, 
sum(case month(biz_order.oacceptancedate) when '4' then 1 else 0 end) as april, 
sum(case month(biz_order.oacceptancedate) when '5' then 1 else 0 end) as may, 
sum(case month(biz_order.oacceptancedate) when '6' then 1 else 0 end) as june, 
sum(case month(biz_order.oacceptancedate) when '7' then 1 else 0 end) as july, 
sum(case month(biz_order.oacceptancedate) when '8' then 1 else 0 end) as august, 
sum(case month(biz_order.oacceptancedate) when '9' then 1 else 0 end) as september, 
sum(case month(biz_order.oacceptancedate) when '10' then 1 else 0 end) as october, 
sum(case month(biz_order.oacceptancedate) when '11' then 1 else 0 end) as november, 
sum(case month(biz_order.oacceptancedate) when '12' then 1 else 0 end) as december 
from biz_order 
where year(biz_order.oacceptancedate)='2018';

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