如何在Athena（Presto）中合并两条SQL查询语句？

可以将两条查询合并，核心思路是先计算出每个target_port_list对应的diff值，再将其与第二条带条件的统计查询通过target_port_list关联，从而在每条统计结果旁展示对应的diff。

以下是合并后的SQL示例（使用CTE语法，可读性更强）：

WITH port_time_diff AS (
    SELECT 
        target_port_list,
        max(CAST(From_iso8601_timestamp(time) AS timestamp)) - min(CAST(From_iso8601_timestamp(time) AS timestamp)) AS "diff"
    FROM alb_logs
    GROUP BY target_port_list
)
SELECT 
    stats.target_port_list,
    stats.elb_status_code,
    stats.cnt,
    port_time_diff.diff
FROM (
    SELECT 
        target_port_list,
        elb_status_code,
        count(*) AS cnt 
    FROM alb_logs
    WHERE request_url = 'https://register.yahoo.in:443/ABC/Registration/Account/Login'
    GROUP BY target_port_list, elb_status_code
) stats
JOIN port_time_diff ON stats.target_port_list = port_time_diff.target_port_list;

如果需要保留第一条查询中的min_date和max_date，只需在CTE的SELECT语句中添加这两个字段，再在最终的SELECT中选取即可。

内容的提问来源于stack exchange，提问作者shantanuo