Mysqli PHP 查询计数

Question

我怎样才能查询这个并得到这种结果丰田(3)？ 这是我的数据库结构。

Make   | Model | Total Cars |

Toyota | Vios  |  1         |

Toyota | Hilux |  2         |

Answer 1

您可以将 sum 与 group by 结合使用来计算特定品牌的库存。

select sum(totalcars) from cars group by make

演示:http://sqlfiddle.com/#!9/d6503/1

要包含 make，请将其添加到 select 查询中:

select sum(totalcars), make from cars group by make

http://sqlfiddle.com/#!9/d6503/2