mysql - 根据一列的信息删除重复项

Question

我想消除基于公司 ID 的重复。我不在乎模型名称下的哪些记录将被删除/保留。

我有这个结果:

+------------+------------------+
| company id | model name       |
+------------+------------------+
|    1       | chevrolet camaro |
|    1       | chevrolet spark  |
|    1       | chevrolet cruze  |
|    2       | mercedes c class |
|    2       | mercedes E class |
+------------+------------------+

我想得到这些结果:

+------------+------------------+
| company id | model name       |
+------------+------------------+
|    1       | chevrolet camaro |
|    2       | mercedes c class |
+------------+------------------+

或者这些结果(重点是我不关心哪个模型名称将被消除):

+------------+------------------+
| company id | model name       |
+------------+------------------+
|    1       | chevrolet spark  |
|    2       | mercedes E class |
+------------+------------------+

我应该做什么？

Answer 1

您可以使用分组依据:

select companyid, min(modelname) as modelname
from t
group b companyid;