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Question

您好我有两个SQL查询

查询1：

Select Year, country, state, city, sales from db.sales1 (for current Year)

查询2：

Select Year, country, state, city, sales from db.sales2(For last 4 years)

要求： 从以上2个查询中选择Current Yr，Country，City，Sales_current，Sales_yr2015，Sales_yr2016。

我该怎么做？

由于

Answer 1

您正在寻找UNION ALL

Select Year, country, state, city, sales from db.sales1 
UNION ALL
Select Year, country, state, city, sales from db.sales2

或者，如果您想要更精简的报告

SELECT country, state, city,
       SUM( CASE WHEN Year = 2015 THEN Sales ELSE 0 END) as Sales_yr2015,
       SUM( CASE WHEN Year = 2016 THEN Sales ELSE 0 END) as Sales_yr2016
FROM (
        Select Year, country, state, city, sales from db.sales1 
        UNION ALL
        Select Year, country, state, city, sales from db.sales2
    ) T
GROUP BY country, state, city