我想在数据库中收到一些电子邮件,每封电子邮件都有一个状态。所有可能的状态都存储在表中,它们都具有权限(例如显示,编辑,删除等)。这些电子邮件不是通过网站拥有权限的用户,而是用户添加的电子邮件列表。
这是表结构:
电子邮件表
CREATE TABLE IF NOT EXISTS `email__email` ( `email_id` int(11) NOT NULL AUTO_INCREMENT, `created` timestamp NULL DEFAULT NULL, `updated` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP, `user_fk` int(11) NOT NULL, `status_fk` tinyint(2) NOT NULL, `language` enum('fr','en') COLLATE utf8_unicode_ci DEFAULT NULL, `email` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, `firstName` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, `lastName` varchar(100) COLLATE utf8_unicode_ci DEFAULT NULL, `companyName` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL, `gender` enum('f','m') COLLATE utf8_unicode_ci DEFAULT NULL, PRIMARY KEY (`email_id`), UNIQUE KEY `user_email` (`user_fk`,`email`), KEY `user_fk` (`user_fk`), KEY `created` (`created`), KEY `status_fk` (`status_fk`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=3031492 ;
状态表
CREATE TABLE IF NOT EXISTS `email__status` ( `status_id` int(11) NOT NULL AUTO_INCREMENT, `name_fr` varchar(50) COLLATE utf8_unicode_ci DEFAULT NULL, `name_en` varchar(50) COLLATE utf8_unicode_ci DEFAULT NULL, `description_fr` varchar(150) COLLATE utf8_unicode_ci DEFAULT NULL, `description_en` varchar(150) COLLATE utf8_unicode_ci DEFAULT NULL, `permShow` tinyint(1) NOT NULL DEFAULT '0', `permSend` tinyint(1) NOT NULL DEFAULT '0', `permEdit` tinyint(1) NOT NULL DEFAULT '0', `permDelete` tinyint(1) NOT NULL DEFAULT '0', `permImport` tinyint(1) NOT NULL DEFAULT '0', PRIMARY KEY (`status_id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=7 ;
这是使用EXPLAIN的慢查询:
SELECT EE.*, ES.name_fr AS statusName, ES.description_fr AS statusDescription, ES.permShow, ES.permSend, ES.permEdit, ES.permDelete, ES.permImport , (SELECT GROUP_CONCAT(CONVERT(CONCAT(GC.name, '~', GC.group_id), CHAR(255)) SEPARATOR ',') FROM `group` GC INNER JOIN group_email GEC ON GEC.group_fk = GC.group_id WHERE GEC.email_fk = EE.email_id AND GC.deleted = 0) AS groups FROM `email__email` EE INNER JOIN email__status ES ON EE.status_fk = ES.status_id WHERE 1 = 1 AND EE.user_fk = 54 AND ES.permShow = 1 ORDER BY EE.email_id DESC LIMIT 15 EXTRA ID KEY KEY_LEN POSSIBLE_KEYS REF ROWS SELECT_TYPE TABLE TYPE Using temporary; Using filesort 1 user_email 4 user_email,user_fk,status_fk const 180681 PRIMARY EE ref Using where; Using join buffer 1 [empty string] [empty string] PRIMARY [empty string] 6 PRIMARY ES ALL Using index 2 email_fk 4 group_email,group_fk,email_fk mailing_dev.EE.email_id 1 DEPENDENT SUBQUERY GEC ref Using where 2 PRIMARY 4 PRIMARY mailing_dev.GEC.group_fk 1 DEPENDENT SUBQUERY GC eq_ref
以下是使用EXPLAIN的快速查询:
SELECT EE.* , (SELECT GROUP_CONCAT(CONVERT(CONCAT(GC.name, '~', GC.group_id), CHAR(255)) SEPARATOR ',') FROM `group` GC INNER JOIN group_email GEC ON GEC.group_fk = GC.group_id WHERE GEC.email_fk = EE.email_id AND GC.deleted = 0) AS groups FROM `email__email` EE WHERE 1 = 1 AND EE.user_fk = 54 AND EXISTS(SELECT permShow FROM email__status WHERE status_id = EE.status_fk AND permShow = 1) ORDER BY EE.email_id DESC LIMIT 15 EXTRA ID KEY KEY_LEN POSSIBLE_KEYS REF ROWS SELECT_TYPE TABLE TYPE Using where 1 PRIMARY 4 user_email,user_fk [empty string] 270 PRIMARY EE index Using where 3 PRIMARY 4 PRIMARY mailing_dev.EE.status_fk 1 DEPENDENT SUBQUERY email__status eq_ref Using index 2 email_fk 4 group_email,group_fk,email_fk mailing_dev.EE.email_id 1 DEPENDENT SUBQUERY GEC ref Using where 2 PRIMARY 4 PRIMARY mailing_dev.GEC.group_fk 1 DEPENDENT SUBQUERY GC eq_ref
两个查询之间存在很大差异,但第二个查询没有给出我需要获取的两个重要列。我可以做子查询来获取它们,就像连接一样,但是,我仍然不希望每个子查询都有很多子查询...有什么想法可以改进这个吗?
由于
答案 0 :(得分:0)
email__email.status_fk
是一个tinyint,但email__status.status_id
是一个int(11)。
这可能会影响你的INNER JOIN。更改一种或另一种数据类型,然后重试。