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Mysql SQL:如何获取不同的值及其';s在单独的列中计数_Mysql_Sql_Count - Fatal编程技术网

Mysql SQL:如何获取不同的值及其';s在单独的列中计数

Mysql SQL:如何获取不同的值及其';s在单独的列中计数,mysql,sql,count,Mysql,Sql,Count,我有一个MySQL表,其列名为“level”,如下所示 | level ----------- | High | High | Medium | Low | Low | Medium 从一个MS图表(pie)控件数据源的查询中输出如下表时,如何计算每个值出现的次数 level | count --------------- High | 1 Medium | 4 Low | 2 按级别分组。聚合函数,如count()适用于每个组 select level, count(*) as

我有一个MySQL表,其列名为“level”,如下所示

| level
-----------
| High
| High
| Medium
| Low
| Low
| Medium
从一个MS图表(pie)控件数据源的查询中输出如下表时,如何计算每个值出现的次数

level  | count
---------------
High   | 1
Medium | 4
Low    | 2

级别分组
。聚合函数,如
count()
适用于每个组

select level, count(*) as cnt
from your_table
group by level