Update 1179.(Easy) Reformat Department Table.sql

Database/1179.(Easy) Reformat Department Table.sql

@@ -1,8 +1,18 @@
 /****************************************************************************************************
 1179. Reformat Department Table
+1179. 重新格式化部门表
 
 Difficulty: Easy
 
+SQL Schema:
+Create table If Not Exists Department (id int, revenue int, month varchar(5))
+Truncate table Department
+insert into Department (id, revenue, month) values ('1', '8000', 'Jan')
+insert into Department (id, revenue, month) values ('2', '9000', 'Jan')
+insert into Department (id, revenue, month) values ('3', '10000', 'Feb')
+insert into Department (id, revenue, month) values ('1', '7000', 'Feb')
+insert into Department (id, revenue, month) values ('1', '6000', 'Mar')
+
 Table: Department
 +---------------+---------+
 | Column Name   | Type    |
@@ -14,8 +24,12 @@ Table: Department
 (id, month) is the primary key of this table.
 The table has information about the revenue of each department per month.
 The month has values in ["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"].
+(id, month) 是表的联合主键。
+这个表格有关于每个部门每月收入的信息。
+月份（month）可以取下列值 ["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"]。
 
 Write an SQL query to reformat the table such that there is a department id column and a revenue column for each month.
+编写一个 SQL 查询来重新格式化表，使得新的表中有一个部门 id 列和一些对应 每个月 的收入（revenue）列。
 
 The query result format is in the following example:
 
@@ -40,10 +54,11 @@ Result table:
 +------+-------------+-------------+-------------+-----+-------------+
 
 Note that the result table has 13 columns (1 for the department id + 12 for the months).
-
+注意，结果表有 13 列 (1个部门 id 列 + 12个月份的收入列)。
 ****************************************************************************************************/
 
 
+--Method2:
 SELECT
     id,
     SUM(IIF(month = 'Jan', revenue, null)) AS Jan_Revenue,
@@ -61,3 +76,21 @@ SELECT
 FROM Department
 GROUP BY id
 
+
+/****************************************************************************************************/
+
+
+--Method2: 
+SELECT id, 
+       [Jan] AS [Jan_Revenue], [Feb] AS [Feb_Revenue], [Mar] AS [Mar_Revenue],
+	   [Apr] AS [Apr_Revenue], [May] AS [May_Revenue], [Jun] AS [Jun_Revenue],
+	   [Jul] AS [Jul_Revenue], [Aug] AS [Aug_Revenue], [Sep] AS [Sep_Revenue],
+	   [Oct] AS [Oct_Revenue], [Nov] AS [Nov_Revenue], [Dec] AS [Dec_Revenue] 
+FROM Department 
+PIVOT (
+    SUM(revenue) 
+    FOR month 
+    IN([Jan],[Feb],[Mar],[Apr],[May],[Jun],[Jul],[Aug],[Sep],[Oct],[Nov],[Dec])
+)AS T
+
+