力扣（leetcode）1148和1179题（MySQL）-编程知识

力扣（leetcode）1148和1179题（MySQL）

1148.文章浏览I

题目链接：1148.文章浏览I
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解答

# Write your MySQL query statement below
select distinct author_id as id 
from Views 
where author_id=viewer_id 
order by id;

1179.重新格式化部门表

题目链接：1179.重新格式化部门表
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解答

# Write your MySQL query statement below
select id,
sum(case when month='Jan' then revenue end) Jan_Revenue,
sum(case when month='Feb' then revenue end) Feb_Revenue,
sum(case when month='Mar' then revenue end) Mar_Revenue,
sum(case when month='Apr' then revenue end) Apr_Revenue,
sum(case when month='May' then revenue end) May_Revenue,
sum(case when month='Jun' then revenue end) Jun_Revenue,
sum(case when month='Jul' then revenue end) Jul_Revenue,
sum(case when month='Aug' then revenue end) Aug_Revenue,
sum(case when month='Sep' then revenue end) Sep_Revenue,
sum(case when month='Oct' then revenue end) Oct_Revenue,
sum(case when month='Nov' then revenue end) Nov_Revenue,
sum(case when month='Dec' then revenue end) Dec_Revenue
from Department group by id order by id;