Mysql Sql在仍然具有所有行值的情况下计算发生次数

这是我所在部门的某个人提出的请求，但我在编写时遇到了一些问题，即既要在列中显示出现的总数，又要保留行

为简单起见，请使用如下表格：

Name    Location
Dave      Ohio
Sam       Ohio 
James    Virginia 
Fred     Idaho 
Cindy   Virginia 
John     Ohio

Name   Location   Total 
Dave   Ohio        3
Sam    Ohio        3
John   Ohio        3
James  Virginia    2
Cindy  Virginia    2
Fred   Idaho       1

但我需要它看起来像这样：

Name    Location
Dave      Ohio
Sam       Ohio 
James    Virginia 
Fred     Idaho 
Cindy   Virginia 
John     Ohio

Name   Location   Total 
Dave   Ohio        3
Sam    Ohio        3
John   Ohio        3
James  Virginia    2
Cindy  Virginia    2
Fred   Idaho       1

因此，我的尝试是：

select Name, Location, count(Location) as 'Total'
from table1
group by Location

给我

Name    Location    Total
Fred    Idaho         1
Dave    Ohio          1
John    Ohio          1
Sam     Ohio          1
Cindy   Virginia      1
James   Virginia      1

---

您可以尝试这样做，编写一个子查询，通过

Location

获取

COUNT

，然后self

JOIN

SELECT 
    t.Name,t.Location,t1.Total
FROM 
    T t 
INNER JOIN 
    (SELECT Location,count(*) Total
     FROM T
     GROUP BY Location) t1 ON t.Location = t1.Location
ORDER BY 
    t1.Total DESC

SQLfiddle：

结果

|  Name | Location | Total |
+-------+----------+-------+
|   Sam |     Ohio |     3 |
|  John |     Ohio |     3 |
|  Dave |     Ohio |     3 |
| James | Virginia |     2 |
| Cindy | Virginia |     2 |
|  Fred |    Idaho |     1 |

---

您可以尝试这样做，编写一个子查询，通过

Location

获取

COUNT

，然后self

JOIN

SELECT 
    t.Name,t.Location,t1.Total
FROM 
    T t 
INNER JOIN 
    (SELECT Location,count(*) Total
     FROM T
     GROUP BY Location) t1 ON t.Location = t1.Location
ORDER BY 
    t1.Total DESC

SQLfiddle：

结果

|  Name | Location | Total |
+-------+----------+-------+
|   Sam |     Ohio |     3 |
|  John |     Ohio |     3 |
|  Dave |     Ohio |     3 |
| James | Virginia |     2 |
| Cindy | Virginia |     2 |
|  Fred |    Idaho |     1 |

---

您可以使用窗口函数

select distinct name, location, count(*) over(partition by location) 
from table1

---

这可以从

MySQL>=8

使用窗口函数

select distinct name, location, count(*) over(partition by location) 
from table1

---

这适用于

MySQL>=8

您使用的是什么风格的SQL？您使用的是什么风格的SQL？