Sql h其他桌子和扼流圈。此外,通过让“和”部分(如日期)直接指向那些左连接,这些连接简化了WHERE,正如您所看到的。。。正如您在where for NULL或它存在时所做的那样,只应用于特定的连接。。。保持房间清洁
此外,通过保持关系的直接性和缩进性,使其与所加入的内容相对应,更容易理解与何处相关的内容Sql h其他桌子和扼流圈。此外,通过让“和”部分(如日期)直接指向那些左连接,这些连接简化了WHERE,正如您所看到的。。。正如您在where for NULL或它存在时所做的那样,只应用于特定的连接。。。保持房间清洁,sql,mysql,performance,join,Sql,Mysql,Performance,Join,此外,通过保持关系的直接性和缩进性,使其与所加入的内容相对应,更容易理解与何处相关的内容 另外,我还想看看最后的“解释”并看看它有什么结果。tblvideources.videoID--这个专栏上有索引吗?与t过滤器上的相关列相同?是的,我相信是这样。检查我的编辑,因为我已经提供了一些进一步的信息。如果包括加入,但排除组_CONCAT,会发生什么情况?我知道这会给你带来不正确的结果,但我想知道与连接s和组相关的性能是否有机会缩小问题(一些“主”表+两次连接的表)?你的内部连接t语言为l。。。没有
另外,我还想看看最后的“解释”并看看它有什么结果。
tblvideources.videoID
--这个专栏上有索引吗?与t过滤器
上的相关列相同?是的,我相信是这样。检查我的编辑,因为我已经提供了一些进一步的信息。如果包括加入
,但排除组_CONCAT
,会发生什么情况?我知道这会给你带来不正确的结果,但我想知道与连接
s和组
相关的性能是否有机会缩小问题(一些“主”表+两次连接的表)?你的内部连接t语言
为l
。。。没有对相应表的显式引用,但在where子句中显示了不同别名“cl”、“kl”、“vl”哦,天哪,您修复了它。现在大约是0.01秒。只是想知道,你认为是直连接使事情更快还是ON子句包含一些WHERE语句?一个正直的人能做什么?@lhnz,澄清了正直的人的回答。。。看一看。再次检查主要问题。:)
SELECT `c`.`categoryID`,
`cl`.`name` AS `category_name`,
`v`.*,
TRUE AS `categoried`,
GROUP_CONCAT(DISTINCT t_v.iso_3166_1_alpha_2) AS `video_territories`,
GROUP_CONCAT(DISTINCT t_c.iso_3166_1_alpha_2) AS `category_territories`,
`vl`.*,
GROUP_CONCAT(DISTINCT kl.name) AS `keywords`
FROM `tblCategories` AS `c`
INNER JOIN `tblCategoryLocalisedData` AS `cl` ON c.categoryID = cl.categoryID
LEFT JOIN `tblCategoryDurations` AS `cd` ON c.categoryID = cd.categoryID
LEFT JOIN `tblCategoryRules` AS `cr` ON c.categoryID = cr.categoryID
LEFT JOIN `tblCategoryVideos` AS `cv` ON c.categoryID = cv.categoryID
LEFT JOIN `tblVideos` AS `v` ON cv.videoID = v.videoID
LEFT JOIN `tblVideoTerritories` AS `vt` ON vt.videoID = v.videoID
LEFT JOIN `tblCategoryTerritories` AS `ct` ON ct.categoryID = c.categoryID
INNER JOIN `tblTerritories` AS `t_v` ON t_v.territoryID = vt.territoryID
INNER JOIN `tblTerritories` AS `t_c` ON t_c.territoryID = ct.territoryID
INNER JOIN `tblVideoLocalisedData` AS `vl` ON vl.videoID = v.videoID
LEFT JOIN `tblVideoKeywords` AS `vk` ON v.videoID = vk.videoID
LEFT JOIN `tblKeywords` AS `k` ON vk.keywordID = k.keywordID
LEFT JOIN `tblKeywordLocalisedData` AS `kl` ON kl.keywordID = k.keywordID
INNER JOIN `tblLanguages` AS `l`
WHERE (cv.disabled IS NULL)
AND (cd.start_date < NOW() OR cd.start_date IS NULL)
AND (cd.end_date > NOW() OR cd.end_date IS NULL)
AND (cr.name IS NULL)
AND (l.languageID = cl.languageID OR cl.languageID IS NULL)
AND (l.languageID = kl.languageID OR kl.languageID IS NULL)
AND (l.languageID = vl.languageID OR vl.languageID IS NULL)
AND (l.iso_639_1 = 'en')
GROUP BY `v`.`videoID`, `c`.`categoryID`
ORDER BY `c`.`categoryID` ASC
+----+-------------+-------+--------+--------------------------------------------------------------------------------------+-----------------------------------------+---------+------------------------+------+----------------------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+--------+--------------------------------------------------------------------------------------+-----------------------------------------+---------+------------------------+------+----------------------------------------------+
| 1 | SIMPLE | cv | ALL | fk_tblCategoryVideos_tblCategories1,fk_tblCategoryVideos_tblVideos1 | NULL | NULL | NULL | 2 | Using where; Using temporary; Using filesort |
| 1 | SIMPLE | c | eq_ref | PRIMARY | PRIMARY | 4 | db.cv.categoryID | 1 | Using index |
| 1 | SIMPLE | cd | ref | fk_tblCategoryDurations_tblCategories | fk_tblCategoryDurations_tblCategories | 4 | db.cv.categoryID | 1 | Using where |
| 1 | SIMPLE | cr | ref | fk_tblCategoryRules_tblCategories1 | fk_tblCategoryRules_tblCategories1 | 4 | db.cv.categoryID | 1 | Using where; Not exists |
| 1 | SIMPLE | vt | ref | fk_tblVideoTerritories_tblVideos1,fk_tblVideoTerritories_tblTerritories1 | fk_tblVideoTerritories_tblVideos1 | 4 | db.cv.videoID | 1 | Using where |
| 1 | SIMPLE | t_v | eq_ref | PRIMARY | PRIMARY | 4 | db.vt.territoryID | 1 | |
| 1 | SIMPLE | v | eq_ref | PRIMARY | PRIMARY | 4 | db.vt.videoID | 1 | Using where |
| 1 | SIMPLE | vk | ref | fk_tblVideoKeywords_tblVideos1 | fk_tblVideoKeywords_tblVideos1 | 4 | db.cv.videoID | 6 | |
| 1 | SIMPLE | k | eq_ref | PRIMARY | PRIMARY | 4 | db.vk.keywordID | 1 | Using index |
| 1 | SIMPLE | kl | ref | fk_tblKeywordLocalisedData_tblKeywords1 | fk_tblKeywordLocalisedData_tblKeywords1 | 4 | db.k.keywordID | 1 | |
| 1 | SIMPLE | cl | ALL | fk_tblCategoryLocalisedData_tblCategories1,fk_tblCategoryLocalisedData_tblLanguages1 | NULL | NULL | NULL | 5 | Using where; Using join buffer |
| 1 | SIMPLE | l | eq_ref | PRIMARY | PRIMARY | 4 | db.cl.languageID | 1 | Using where |
| 1 | SIMPLE | ct | ALL | fk_tblCategoryTerritories_tblCategories1,fk_tblCategoryTerritories_tblTerritories1 | NULL | NULL | NULL | 2 | Using where; Using join buffer |
| 1 | SIMPLE | vl | ALL | fk_tblVideoLocalisedData_tblLanguages1,fk_tblVideoLocalisedData_tblVideos1 | NULL | NULL | NULL | 9 | Using where; Using join buffer |
| 1 | SIMPLE | t_c | eq_ref | PRIMARY | PRIMARY | 4 | db.ct.territoryID | 1 | |
+----+-------------+-------+--------+--------------------------------------------------------------------------------------+-----------------------------------------+---------+------------------------+------+----------------------------------------------+
CREATE TABLE `tblVideoTerritories` (
`videoTerritoryID` int(10) unsigned NOT NULL AUTO_INCREMENT,
`videoID` int(10) unsigned NOT NULL,
`territoryID` int(10) unsigned NOT NULL,
PRIMARY KEY (`videoTerritoryID`),
KEY `fk_tblVideoTerritories_tblVideos1` (`videoID`),
KEY `fk_tblVideoTerritories_tblTerritories1` (`territoryID`),
CONSTRAINT `fk_tblVideoTerritories_tblTerritories1` FOREIGN KEY (`territoryID`) REFERENCES `tblTerritories` (`territoryID`) ON DELETE NO ACTION ON UPDATE NO ACTION,
CONSTRAINT `fk_tblVideoTerritories_tblVideos1` FOREIGN KEY (`videoID`) REFERENCES `tblVideos` (`videoID`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci
CREATE TABLE `tblCategoryTerritories` (
`categoryTerritoryID` int(10) unsigned NOT NULL AUTO_INCREMENT,
`categoryID` int(10) unsigned NOT NULL,
`territoryID` int(10) unsigned NOT NULL,
PRIMARY KEY (`categoryTerritoryID`),
KEY `fk_tblCategoryTerritories_tblCategories1` (`categoryID`),
KEY `fk_tblCategoryTerritories_tblTerritories1` (`territoryID`),
CONSTRAINT `fk_tblCategoryTerritories_tblCategories1` FOREIGN KEY (`categoryID`) REFERENCES `tblCategories` (`categoryID`) ON DELETE NO ACTION ON UPDATE NO ACTION,
CONSTRAINT `fk_tblCategoryTerritories_tblTerritories1` FOREIGN KEY (`territoryID`) REFERENCES `tblTerritories` (`territoryID`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci
CREATE TABLE `tblTerritories` (
`territoryID` int(10) unsigned NOT NULL AUTO_INCREMENT,
`iso_3166_1_alpha_2` char(2) COLLATE utf8_unicode_ci DEFAULT NULL,
`iso_3166_1_alpha_3` char(3) COLLATE utf8_unicode_ci DEFAULT NULL,
`defaultLanguageID` int(10) unsigned DEFAULT NULL,
PRIMARY KEY (`territoryID`),
KEY `fk_tblTerritories_tblLanguages1` (`defaultLanguageID`),
KEY `iso_3166_1_alpha_2` (`iso_3166_1_alpha_2`),
CONSTRAINT `fk_tblTerritories_tblLanguages1` FOREIGN KEY (`defaultLanguageID`) REFERENCES `tblLanguages` (`languageID`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci
SELECT `c`.`categoryID`,
`v`.`videoID`,
GROUP_CONCAT(DISTINCT t_v.iso_3166_1_alpha_2) AS `video_territories`,
GROUP_CONCAT(DISTINCT t_c.iso_3166_1_alpha_2) AS `category_territories`
FROM `tblCategories` AS `c`
LEFT JOIN `tblCategoryVideos` AS `cv` ON c.categoryID = cv.categoryID
LEFT JOIN `tblVideos` AS `v` ON cv.videoID = v.videoID
LEFT JOIN `tblVideoTerritories` AS `vt` ON vt.videoID = v.videoID
LEFT JOIN `tblCategoryTerritories` AS `ct` ON ct.categoryID = c.categoryID
INNER JOIN `tblTerritories` AS `t_v` ON t_v.territoryID = vt.territoryID
INNER JOIN `tblTerritories` AS `t_c` ON t_c.territoryID = ct.territoryID
GROUP BY `v`.`videoID`, `c`.`categoryID`
SELECT `c`.`categoryID`,
`cl`.`name` AS `category_name`,
`v`.*,
TRUE AS `categoried`,
GROUP_CONCAT(DISTINCT t_v.iso_3166_1_alpha_2) AS `video_territories`,
GROUP_CONCAT(DISTINCT t_c.iso_3166_1_alpha_2) AS `category_territories`,
`vl`.*,
GROUP_CONCAT(DISTINCT kl.name) AS `keywords`
FROM `tblCategories` AS `c`
INNER JOIN `tblCategoryLocalisedData` AS `cl` ON c.categoryID = cl.categoryID
LEFT JOIN `tblCategoryDurations` AS `cd` ON c.categoryID = cd.categoryID
LEFT JOIN `tblCategoryRules` AS `cr` ON c.categoryID = cr.categoryID
LEFT JOIN `tblCategoryVideos` AS `cv` ON c.categoryID = cv.categoryID
LEFT JOIN `tblVideos` AS `v` ON cv.videoID = v.videoID
LEFT JOIN `tblVideoTerritories` AS `vt` ON vt.videoID = v.videoID
LEFT JOIN `tblCategoryTerritories` AS `ct` ON ct.categoryID = c.categoryID
INNER JOIN `tblTerritories` AS `t_v` ON t_v.territoryID = vt.territoryID
INNER JOIN `tblTerritories` AS `t_c` ON t_c.territoryID = ct.territoryID
INNER JOIN `tblVideoLocalisedData` AS `vl` ON vl.videoID = v.videoID
LEFT JOIN `tblVideoKeywords` AS `vk` ON v.videoID = vk.videoID
LEFT JOIN `tblKeywords` AS `k` ON vk.keywordID = k.keywordID
LEFT JOIN `tblKeywordLocalisedData` AS `kl` ON kl.keywordID = k.keywordID
INNER JOIN `tblLanguages` AS `l` ON (l.languageID = cl.languageID OR cl.languageID IS NULL) AND (l.languageID = kl.languageID OR kl.languageID IS NULL) AND (l.languageID = vl.languageID OR vl.languageID IS NULL)
WHERE (cv.disabled IS NULL)
AND (cd.start_date < NOW() OR cd.start_date IS NULL)
AND (cd.end_date > NOW() OR cd.end_date IS NULL)
AND (cr.name IS NULL) AND (l.iso_639_1 = 'en')
GROUP BY `v`.`videoID`, `c`.`categoryID`
ORDER BY `c`.`categoryID` ASC
CREATE TABLE `tblVideoKeywords` (
`videoKeywordID` int(10) unsigned NOT NULL AUTO_INCREMENT,
`videoID` int(10) unsigned NOT NULL,
`keywordID` int(10) unsigned NOT NULL,
PRIMARY KEY (`videoKeywordID`),
KEY `fk_tblVideoKeywords_tblVideos1` (`videoID`),
KEY `fk_tblVideoKeywords_tblKeywords1` (`keywordID`),
CONSTRAINT `fk_tblVideoKeywords_tblKeywords1` FOREIGN KEY (`keywordID`) REFERENCES `tblKeywords` (`keywordID`) ON DELETE NO ACTION ON UPDATE NO ACTION,
CONSTRAINT `fk_tblVideoKeywords_tblVideos1` FOREIGN KEY (`videoID`) REFERENCES `tblVideos` (`videoID`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB AUTO_INCREMENT=18 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci
+----+-------------+---------+--------+--------------------------------------------------------------------------------------+-----------------------------------------+---------+------------------------+------+----------------------------------------------+
| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+---------+--------+--------------------------------------------------------------------------------------+-----------------------------------------+---------+------------------------+------+----------------------------------------------+
| 1 | SIMPLE | c | index | PRIMARY | PRIMARY | 4 | NULL | 3 | Using index; Using temporary; Using filesort |
| 1 | SIMPLE | cl | ALL | fk_tblCategoryLocalisedData_tblCategories1,fk_tblCategoryLocalisedData_tblLanguages1 | NULL | NULL | NULL | 5 | Using where; Using join buffer |
| 1 | SIMPLE | lang_cl | ALL | PRIMARY | NULL | NULL | NULL | 2 | Using where; Using join buffer |
| 1 | SIMPLE | cd | ref | fk_tblCategoryDurations_tblCategories | fk_tblCategoryDurations_tblCategories | 4 | db.c.categoryID | 1 | |
| 1 | SIMPLE | cr | ref | fk_tblCategoryRules_tblCategories1 | fk_tblCategoryRules_tblCategories1 | 4 | db.c.categoryID | 1 | Using where; Not exists |
| 1 | SIMPLE | cv | ALL | fk_tblCategoryVideos_tblCategories1,fk_tblCategoryVideos_tblVideos1 | NULL | NULL | NULL | 2 | Using where; Using join buffer |
| 1 | SIMPLE | ct | ALL | fk_tblCategoryTerritories_tblCategories1,fk_tblCategoryTerritories_tblTerritories1 | NULL | NULL | NULL | 2 | Using where; Using join buffer |
| 1 | SIMPLE | t_c | eq_ref | PRIMARY | PRIMARY | 4 | db.ct.territoryID | 1 | |
| 1 | SIMPLE | v | eq_ref | PRIMARY | PRIMARY | 4 | db.cv.videoID | 1 | Using where |
| 1 | SIMPLE | vt | ref | fk_tblVideoTerritories_tblVideos1,fk_tblVideoTerritories_tblTerritories1 | fk_tblVideoTerritories_tblVideos1 | 4 | db.v.videoID | 1 | Using where |
| 1 | SIMPLE | t_v | eq_ref | PRIMARY | PRIMARY | 4 | db.vt.territoryID | 1 | |
| 1 | SIMPLE | vl | ALL | fk_tblVideoLocalisedData_tblLanguages1,fk_tblVideoLocalisedData_tblVideos1 | NULL | NULL | NULL | 9 | Using where; Using join buffer |
| 1 | SIMPLE | lang_vl | eq_ref | PRIMARY | PRIMARY | 4 | db.vl.languageID | 1 | Using where |
| 1 | SIMPLE | vk | ALL | fk_tblVideoKeywords_tblVideos1,fk_tblVideoKeywords_tblKeywords1 | NULL | NULL | NULL | 15 | Using where; Using join buffer |
| 1 | SIMPLE | k | eq_ref | PRIMARY | PRIMARY | 4 | db.vk.keywordID | 1 | Using where; Using index |
| 1 | SIMPLE | kl | ref | fk_tblKeywordLocalisedData_tblKeywords1,fk_tblKeywordLocalisedData_tblLanguages1 | fk_tblKeywordLocalisedData_tblKeywords1 | 4 | db.k.keywordID | 1 | Using where |
| 1 | SIMPLE | lang_kl | eq_ref | PRIMARY | PRIMARY | 4 | db.kl.languageID | 1 | Using where |
+----+-------------+---------+--------+--------------------------------------------------------------------------------------+-----------------------------------------+---------+------------------------+------+----------------------------------------------+
17 rows in set (0.01 sec)
SELECT STRAIGHT_JOIN
c.categoryID,
cl.name AS category_name,
v.*,
TRUE AS categoried,
GROUP_CONCAT(DISTINCT t_v.iso_3166_1_alpha_2) AS video_territories,
GROUP_CONCAT(DISTINCT t_c.iso_3166_1_alpha_2) AS category_territories,
vl.*,
GROUP_CONCAT(DISTINCT kl.name) AS keywords
FROM
tblCategories AS c
INNER JOIN tblCategoryLocalisedData AS cl
ON c.categoryID = cl.categoryID
INNER JOIN tblLanguages AS lang_cl
ON l.languageID = lang_cl.languageID
AND lang_cl.iso_639_1 = 'en'
LEFT JOIN tblCategoryDurations AS cd
ON c.categoryID = cd.categoryID
AND cd.start_date < NOW()
AND cd.end_date > NOW()
LEFT JOIN tblCategoryRules AS cr
ON c.categoryID = cr.categoryID
LEFT JOIN tblCategoryVideos AS cv
ON c.categoryID = cv.categoryID
LEFT JOIN tblCategoryTerritories AS ct
ON c.categoryID = ct.categoryID
INNER JOIN tblTerritories AS t_c
ON ct.territoryID = t_c.territoryID
LEFT JOIN tblVideos AS v
ON cv.videoID = v.videoID
LEFT JOIN tblVideoTerritories AS vt
ON v.videoID = vt.videoID
INNER JOIN tblTerritories AS t_v
ON vt.territoryID = t_v.territoryID
INNER JOIN tblVideoLocalisedData AS vl
ON v.videoID = vl.videoID
INNER JOIN tblLanguages AS lang_vl
ON vl.languageID = lang_vl.languageID
AND lang_vl.iso_639_1 = 'en'
LEFT JOIN tblVideoKeywords AS vk
ON v.videoID = vk.videoID
LEFT JOIN tblKeywords AS k
ON vk.keywordID = k.keywordID
LEFT JOIN tblKeywordLocalisedData AS kl
ON k.keywordID = kl.keywordID
INNER JOIN tblLanguages AS lang_kl
ON kl.languageID = lang_kl.languageID
AND lang_kl.iso_639_1 = 'en'
WHERE
( cv.disabled IS NULL)
AND ( cr.name IS NULL)
GROUP BY
v.videoID,
c.categoryID
ORDER BY
c.categoryID ASC