SELECT记录WHERE行在特定列上有差异

Question

我有一个数据库表campaign_data.我需要选择customer_id竞选活动中的关税差异.我怎么能用MySQL查询做到这一点.这是一些示例数据.

SQL小提琴架构

| CAMPAIGN_ID | CUSTOMER_ID |    CAMPAIGN_NAME | TARIFF |
---------------------------------------------------------
|           1 |           1 |         Richmond |    100 |
|           2 |           1 | Sutton Coldfield |     75 |
|           3 |           1 |           Putney |    100 |
|           4 |           1 |     Kentish Town |    100 |
|           5 |           1 |           Woking |    100 |
|           6 |           2 |         Chiswick |     90 |
|           7 |           2 |           Ealing |    100 |
|           8 |           2 |           Camden |    100 |
|           9 |           3 |          Croydon |     75 |
|          10 |           3 |         Croydon1 |    100 |
|          11 |           3 |          Archway |    100 |
|          12 |           4 |          Ealing0 |    100 |
|          13 |           4 |         Ealing01 |    100 |
|          14 |           4 |         Ealing02 |    100 |
|          15 |           4 |        Chingford |    100 |
|          16 |           4 |      chingford01 |    100 |

现在您可以看到客户ID 1和3具有不同的关税.我想选择它们并留下客户ID 4,因为它具有相同关税的活动.

期望的输出

| CUSTOMER_ID |
---------------
|           1 |
|           2 |
|           3 |

为了清楚起见,您可以看到客户1有5条记录.如果在他的5个记录中关税是相同的(100)我想避免,但如果关税不是一些,因为4个记录有100个,一个有75个,我想选择.

Answer 1

SELECT customer_id, count(DISTINCT tariff) as tariffs 
FROM campaign_data 
GROUP BY customer_id 
HAVING tariffs > 1