Question

我目前正在处理看起来像这样的SQL查询

SELECT reference.agent_ID, reference.policy_ID, Count(reference.status_ID) AS [Quoted Motor Breakdown] , Sum(IIf([status_ID]=1,1,0)) AS sold
FROM reference
GROUP BY reference.agent_ID, reference.policy_ID
HAVING (((reference.policy_ID)=1));

结果显示如下

Agent| Number of policies quoted for Motor breakdown|number of policies Motor breakdown sold

我想在同一个表中添加更多列，显示剩余策略类型的结果：

reference.policy_ID=2 (Travel), 
reference.policy_ID=3 (Home Insurance)  next to one agent

例如：史密斯先生|引用汽车故障|出售|引用汽车旅行|出售

如果没有针对特定策略类型的引用，我还希望我的查询显示result = 0 任何建议将不胜感激谢谢

Answer 1

我认为你想要条件聚合：

SELECT r.agent_ID,
       SUM(CASE WHEN r.policy_ID = 1 THEN 1 ELSE 0 END) AS [Quoted Motor Breakdown],
       SUM(CASE WHEN r.policy_ID = 1 AND status_ID = 1 THEN 1 ELSE 0 END) AS sold,
       SUM(CASE WHEN r.policy_ID = 2 THEN 1 ELSE 0 END) AS NumTravel,
       SUM(CASE WHEN r.policy_ID = 3 THEN 1 ELSE 0 END) AS NumHomeInsurance
FROM reference r
GROUP BY r.agent_ID;

如果您使用的是MS Access，则需要使用非标准版iif()：

SELECT r.agent_ID,
       SUM(iif(r.policy_ID = 1, 1, 0)) AS [Quoted Motor Breakdown],
       SUM(iif(r.policy_ID = 1 AND status_ID = 1, 1, 0)) AS sold,
       SUM(iif(r.policy_ID = 2, 1, 0)) AS NumTravel,
       SUM(iif(r.policy_ID = 3, 1, 0)) AS NumHomeInsurance
FROM reference as r
GROUP BY r.agent_ID;

在同一个表上使用多个WHERE条件进行SELECTING

1 个答案: