我正在尝试优化此查询。现在需要28秒。
AS曾经在我的查询中丢失。添加后,查询时间减少了20%
SELECT
g.id,
g.adresid,
g.senaryoid,
g.olayid,
g.gonderilecegitarih
FROM
(
SELECT
adresid
FROM
expose2.800_emsenaryolar_emgidenbulten
WHERE
olayid = '3320'
) AS s
RIGHT JOIN expose2.800_emsenaryolar_emgidenbulten AS g ON s.adresid = g.adresid
WHERE
s.adresid IS NULL
AND g.olayid = '2784'
AND g.durum = '1'
AND g.gonderilecegitarih < DATE_SUB(
'2015-05-13 15:40:15',
INTERVAL 1 DAY
)
最佳答案
如果您在子查询中使用s.adresid IS NULL
条件,它将更快地连接,然后更多行...
SELECT
g.id,
g.adresid,
g.senaryoid,
g.olayid,
g.gonderilecegitarih
FROM (
SELECT adresid FROM expose2.800_emsenaryolar_emgidenbulten WHERE olayid = '3320' and s.adresid IS NULL
) AS s
RIGHT JOIN expose2.800_emsenaryolar_emgidenbulten AS g ON s.adresid = g.adresid
AND g.olayid = '2784'
AND g.durum = '1'
AND g.gonderilecegitarih < DATE_SUB(
'2015-05-13 15:40:15',
INTERVAL 1 DAY
)
该查询仍然使用自我联接进行了优化。