So far I have this query
SELECT
COUNT(f.code_id) as item_count,
f.code_desc
FROM
foo f
INNER JOIN foohistory fh ON f.history_id = fh.history_id
WHERE
MONTH(fh.create_dt) = 6
AND YEAR(fh.create_开发者_如何转开发dr) = 2010
GROUP BY
f.code_desc
UNION ALL
SELECT
COUNT(b.code_id) as item_count,
b.code_desc
FROM
bar b
INNER JOIN barhistory bh ON b.history_id = bh.history_id
WHERE
MONTH(bh.create_dt) = 6
AND YEAR(bh.create_dr) = 2010
GROUP BY
b.code_desc
My goal is to UNION these two queries add SUM the 'item_count' columns foreach code_desc. Is this possible?
Without more information about the codes, like if it's possible that codes are mutually exclusive between the two tables, use:
SELECT x.code_desc,
SUM(x.item_count)
FROM (SELECT f.code_desc,
COUNT(f.code_id) as item_count
FROM foo f
JOIN foohistory fh ON f.history_id = fh.history_id
WHERE MONTH(fh.create_dt) = 6
AND YEAR(fh.create_dr) = 2010
GROUP BY f.code_desc
UNION ALL
SELECT b.code_desc,
COUNT(b.code_id) as item_count
FROM bar b
JOIN barhistory bh ON b.history_id = bh.history_id
WHERE MONTH(bh.create_dt) = 6
AND YEAR(bh.create_dr) = 2010
GROUP BY b.code_desc) x
GROUP BY x.code_desc
Yeah, doing something like this
SELECT Sum(unionedTable.item_count)
FROM
(
//your query
) as unionedTable
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