透過在 MySQL 中對日期進行分組來顯示記錄


要對 MySQL 中的日期進行分組,請使用 GROUP BY 子句 −

mysql> create table DemoTable2002
(
   CustomerName varchar(20),
   CustomerShippingDate datetime
);
Query OK, 0 rows affected (0.61 sec)

使用插入命令在表中插入一些記錄 −

mysql> insert into DemoTable2002 values('Chris','2019-01-10');
Query OK, 1 row affected (0.17 sec)
mysql> insert into DemoTable2002 values('David','2018-12-31');
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable2002 values('David','2019-12-16');
Query OK, 1 row affected (0.14 sec)
mysql> insert into DemoTable2002 values('Chris','2018-12-01');
Query OK, 1 row affected (0.12 sec)

使用 select 語句從表中顯示所有記錄 −

mysql> select * from DemoTable2002;

這將生成以下輸出 −

+--------------+----------------------+
| CustomerName | CustomerShippingDate |
+--------------+----------------------+
| Chris        | 2019-01-10 00:00:00  |
| David        | 2018-12-31 00:00:00  |
| David        | 2019-12-16 00:00:00  |
| Chris        | 2018-12-01 00:00:00  |
+--------------+----------------------+
4 rows in set (0.00 sec)

以下是透過對日期進行分組來顯示記錄的查詢 −

mysql> select date(min(CustomerShippingDate)),date(max(CustomerShippingDate)),CustomerName
   from DemoTable2002
   group by CustomerName;

這將生成以下輸出 −

+---------------------------------+---------------------------------+--------------+
| date(min(CustomerShippingDate)) | date(max(CustomerShippingDate)) | CustomerName |
+---------------------------------+---------------------------------+--------------+
| 2018-12-01                      | 2019-01-10                      | Chris        |
| 2018-12-31                      | 2019-12-16                      | David        |
+---------------------------------+---------------------------------+--------------+
2 rows in set (0.00 sec)

更新於: 2020-01-02

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