重用查询结果子查询

我有这个丑陋的查询....重用查询结果子查询

sum(CASE 
     WHEN effective_from_date < '2011-05-24' THEN (rate * (effective_to_date - '2011-05-24' + 1)) 
     WHEN effective_to_date > '2011-05-28' THEN (rate * ('2011-05-28' - effective_from_date + 1)) 
     ELSE (rate * (effective_to_date - effective_from_date + 1)) 
    END 
    ) as price_cal_rate 
     FROM calendar_event 
     WHERE property_rid = (SELECT rid FROM property WHERE web_id = 'T28314') AND 
     ((effective_from_date BETWEEN '2011-05-24' AND '2011-05-28') OR (effective_to_date BETWEEN '2011-05-24' AND '2011-05-28')) 
     AND 
     NOT EXISTS (

     SELECT days_diff FROM (


     SELECT ((effective_from_date - lag(effective_to_date) OVER (PARTITION BY NULL ORDER BY effective_from_date ASC))) AS days_diff, effective_from_date, effective_to_date 
      FROM calendar_event 
      WHERE property_rid = (SELECT rid FROM property WHERE web_id = 'T28314') AND 
     ((effective_from_date BETWEEN '2011-05-26' AND '2011-05-28') OR (effective_to_date BETWEEN '2011-05-26' AND '2011-05-28')) 


     ) AS t WHERE COALESCE(days_diff, 0) > 1 

     ) AND EXISTS (select * from (
      select min(effective_from_date) as min_date, max(effective_to_date) as max_date FROM calendar_event 
     WHERE property_rid = (SELECT rid FROM property WHERE web_id = 'T28314') AND 
     ((effective_from_date BETWEEN '2011-05-24' AND '2011-05-28') OR (effective_to_date BETWEEN '2011-05-24' AND '2011-05-28')) 
     ) as max_min WHERE min_date <= '2011-05-24' and max_date >= '2011-05-28')

查询被计算在日期范围率....查询是好的......但有一个很多查询重复....我想知道是否有存储该子查询的地方

FROM calendar_event 
     WHERE property_rid = (SELECT rid FROM property WHERE web_id = 'T28314') 
AND 
      ((effective_from_date BETWEEN '2011-05-24' AND '2011-05-28') OR (effective_to_date BETWEEN '2011-05-24' AND '2011-05-28'))

的结果，并用它在我的查询的好办法....

来源

2011-05-08 Rob

这可能是什么工作，但它是值得一试。 pgsql非常擅长于在运行时优化看起来像是一次重复的重复。我肯定会比较这两个查询的解释分析输出，以查看当您创建临时表或使用WITH子句时是否更快。查找与，它几乎没有被制作成您所查询的表中的临时表 – 2011-05-08 14:28:20

你可以使用临时表作为“亩太短”的建议泰德但如果你只需要在一个单一的“主”的查询结果，你使用PostgreSQL 8.4或更高版本，你也可以使用with queries

来源

2011-05-08 05:46:52 Eelke

非常感谢球员 – Rob 2011-05-08 07:18:08

重用查询结果子查询

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