通过省略 UNION ALL 来简化查询或重写查询？

Question

SELECT
         '2016 - 17' as 'Years',
         SUM("svalue") as 'Value',
         'Sale' as 'Type',
         "code" as 'FACode',
         'Apr 1 - Jan 31' as 'Period'
FROM  "FCJOIN" 
WHERE    "code"  IN
    (
    SELECT "fccode"
    FROM  "fcdetails" 
    )
 AND    (("year"  = '2016' AND  "month"  >= '04')
 OR ("year"  = '2017' AND   "month"  <= '01'))
GROUP BY  "code" 
UNION ALL
 SELECT
         '2017 - 18' as 'Years',
         SUM("svalue") as 'Value',
         'Sale' as 'Type',
         "code" as 'FACode',
         'Apr 1 - Jan 31' as 'Period'
FROM  "FCJOIN" 
WHERE    "code"  IN
    (
    SELECT "fccode"
    FROM  "fcdetails" 
    )
 AND    (("year"  = '2017' AND  "month"  >= '04')
 OR ("year"  = '2018' AND   "month"  <= '01'))
GROUP BY  "code" 
UNION ALL
 SELECT
         '2018 - 19' as 'Years',
         SUM("svalue") as 'Value',
         'Sale' as 'Type',
         "code" as 'FACode',
         'Apr 1 - Jan 31' as 'Period'
FROM  "FCJOIN" 
WHERE    "code"  IN
    (
    SELECT "fccode"
    FROM  "fcdetails" 
    )
 AND    (("year"  = '2018' AND  "month"  >= '04')
 OR ("year"  = '2019' AND   "month"  <= '01'))
GROUP BY  "code" 
UNION ALL
 SELECT
         '2019 - 20' as 'Years',
         SUM("svalue") as 'Value',
         'Sale' as 'Type',
         "code" as 'FACode',
         'Apr 1 - Jan 31' as 'Period'
FROM  "FCJOIN" 
WHERE    "code"  IN
    (
    SELECT "fccode"
    FROM  "fcdetails" 
    )
 AND    (("year"  = '2019' AND  "month"  >= '04')
 OR ("year"  = '2020' AND   "month"  <= '01'))
GROUP BY  "code"

从上面的查询中，我得到了

期间的 SUM(svalue)

April 2016 - Jan 2017  
April 2017 - Jan 2018  
April 2018 - Jan 2019   
April 2019 - Jan 2020

是否可以简化此查询？我不想要 UNION ALL - 当我在 zoho 中使用此查询时，它们限制了我在完整查询中使用以获得完整结果的 UNION ALL (139) 的总数。有什么方法可以重写上面的查询，从而得到相同的结果。谢谢。

Answer 1

您可以通过构建 Years 值然后按它和 code 进行分组来实现。例如：

WITH yearly AS (
  SELECT CONCAT(CASE WHEN month < 4 THEN year -1  ELSE year END,
                ' - ',
                CASE WHEN month < 4 THEN year ELSE year + 1 END) AS 'Years',
         svalue,
         code AS 'FACode'
  FROM fcjoin
  WHERE code IN (SELECT fccode FROM fcdetails)
  AND month = 1 OR month > 3
)
SELECT Years, 
       SUM(svalue) AS 'Value',
       'Sale' AS 'Type', 
       FACode,
       'Apr 1 - Jan 31' AS 'Period'
FROM yearly
GROUP BY Years, FACode
ORDER BY Years, FACode

Demo on dbfiddle

如果您的环境不支持 CTE，您可以将 yearly 写成子查询：

SELECT Years, 
       SUM(svalue) AS 'Value',
       'Sale' AS 'Type', 
       FACode,
       'Apr 1 - Jan 31' AS 'Period'
FROM (
  SELECT CONCAT(CASE WHEN month < 4 THEN year -1  ELSE year END,
                ' - ',
                CASE WHEN month < 4 THEN year ELSE year + 1 END) AS 'Years',
         svalue,
         code AS 'FACode'
  FROM fcjoin
  WHERE code IN (SELECT fccode FROM fcdetails)
  AND month = 1 OR month > 3
) yearly
GROUP BY Years, FACode
ORDER BY Years, FACode

Demo on dbfiddle

通过省略 UNION ALL 来简化查询或重写查询？

Simplify the query or rewriting the query by omitting UNION ALL?

sql

sql-server

zoho