SQL 如何将两个sql查询合并为一个
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How to combine two sql queries into one
提问by Anthony
How can I combine these two SQL statements?
如何组合这两个 SQL 语句？
SELECT SUM(hits01 + hits02 + hits03 + hits04 + hits05 + hits06 + hits07 + hits08 + hits09) AS 'AEROwiz'
FROM tbl_2011
WHERE appName='AEROwiz'
SELECT SUM(hits10 + hits11 + hits12) AS 'AEROwiz'
FROM tbl_2010
WHERE appName='AEROwiz'
hits10, hits11 and hits12 exist in both tables.
hits10、hits11 和 hits12 存在于两个表中。
回答by Marc B
Use a UNION query - just stuff "UNION" between the two queries:
使用 UNION 查询 - 只是在两个查询之间填充“UNION”：
SELECT SUM(...) AS AEROWiz
FROM ...
UNION
SELECT SUM(...) AS AEROWiz
FROM ...
update
更新
wrap the union in yet another query:
将联合包装在另一个查询中：
SELECT SUM(AEROWiz)
FROM (
.... unioned queries here
) AS child
回答by Anthony
SELECT SUM(hits01 + hits02 + hits03 + hits04 + hits05 + hits06 +
hits07 + hits08 + hits09) AS 'AEROwiz'
FROM tbl_2011
WHERE appName='AEROwiz'
UNION ALL
SELECT SUM(hits10 + hits11 + hits12) AS 'AEROwiz'
FROM tbl_2010
WHERE appName='AEROwiz'
Use UNION ALLas it will allow duplicates, and UNIONwill not put duplicates in the query result. With the SUM()aggregate, I'm guessing there's a good chance of duplication summations, so I'd go with UNION ALLfor this one.
使用UNION ALL因为它允许重复，并且UNION不会在查询结果中放置重复。有了SUM()聚合，我猜重复求和的机会很大，所以我会选择UNION ALL这个。
回答by Mark Byers
You could use two subselects:
您可以使用两个子选择：
SELECT
(
SELECT SUM(hits01 + hits02 + hits03 + hits04 + hits05 + hits06 + hits07 + hits08 + hits09)
FROM tbl_2011
WHERE appName='AEROwiz'
) T1
+
(
SELECT SUM(hits10 + hits11 + hits12)
FROM tbl_2010
WHERE appName='AEROwiz'
) T2
AS AEROwiz
You may also want to consider normalizing your database so that you don't have a table for each year.
您可能还需要考虑规范化您的数据库，以便您没有每年的表。
回答by Arnaud F.
SELECT SUM(hits01 + hits02 + hits03 + hits04 + hits05 + hits06 +
hits07 + hits08 + hits09 + t2010.hits10 + t2010.hits11 + t2010.hits12) AS 'AEROwiz'
FROM tbl_2010 t2010
JOIN tbl_2011 t2011 ON t2010.appName = t2011.appName
WHERE t2010.appName='AEROwiz'
