大家好，我有一个MySQL查询，可以从多个表中获取数据。这是我的查询
SELECT
user_id as id,
user_name as name,
user_phone as phone,
user_email as email,
user_address1 as address1,
user_address2 as address2,
user_city as city,
user_state as state,
user_country as country,
user_available as available,
user_location as location,
user_latitude as latitude,
user_longitude as longitude,
user_description as description,
user_company as company,
user_gender as gender,
(SELECT MIN(service_price) FROM service WHERE service.user_id = a.user_id) as price,
(SELECT service_recomanded FROM service WHERE service.user_id = a.user_id ORDER BY service.service_price ASC LIMIT 1) as recomandad,
verified_email,
verified_facebook,
verified_phone,
verified_twitter,
(SELECT providerphoto_name FROM providerphoto WHERE providerphoto.user_id = a.user_id ORDER BY providerphoto_order ASC LIMIT 1 ) as photo,
(SELECT ROUND( AVG(review_rate),2) FROM review WHERE review.user_id = a.user_id ) AS rate,
(SELECT service_ICOC FROM service WHERE service.user_id = a.user_id ORDER BY service_price ASC LIMIT 1) as type
FROM
user a
WHERE a.user_type = 'provider'
AND a.user_active=1
AND a.user_deleted=0
它从用户表，服务表，评论表和providerphoto表中获取数据。它也可以，但执行时间非常慢。我想让它成为一个单一的查询，并避免内部五个查询可以快速运行它。有什么帮助吗？
表结构。
--
-- Table structure for table `providerphoto`
--
CREATE TABLE IF NOT EXISTS `providerphoto` (
`providerphoto_id` int(11) NOT NULL AUTO_INCREMENT,
`user_id` int(11) NOT NULL,
`providerphoto_file` varchar(256) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
`providerphoto_name` varchar(256) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
`providerphoto_date` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
`providerphoto_order` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`providerphoto_id`),
KEY `user_id` (`user_id`),
KEY `providerphoto` (`user_id`,`providerphoto_name`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=487 ;
-- --------------------------------------------------------
--
-- Table structure for table `review`
--
CREATE TABLE IF NOT EXISTS `review` (
`review_id` int(11) NOT NULL AUTO_INCREMENT,
`review_title` varchar(256) COLLATE utf8_unicode_ci NOT NULL,
`user_id` int(11) NOT NULL,
`review_date` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP,
`review_content` text COLLATE utf8_unicode_ci NOT NULL,
`review_user_id` int(11) NOT NULL,
`review_rate` int(10) NOT NULL DEFAULT '1',
`review_tip` int(11) NOT NULL DEFAULT '0',
`service_booked` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`review_id`),
KEY `user_id` (`user_id`),
KEY `review_date` (`review_date`),
KEY `review_user_id` (`review_user_id`),
KEY `review_rate` (`review_rate`),
KEY `review_tip` (`review_tip`),
KEY `service_booked` (`service_booked`),
KEY `review` (`user_id`,`review_rate`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=97 ;
-- --------------------------------------------------------
--
-- Table structure for table `service`
--
CREATE TABLE IF NOT EXISTS `service` (
`service_id` int(11) NOT NULL AUTO_INCREMENT,
`service_name` varchar(45) COLLATE utf8_unicode_ci DEFAULT NULL,
`user_id` int(11) DEFAULT NULL,
`service_created_by` int(11) NOT NULL DEFAULT '0',
`service_ICOC` varchar(256) COLLATE utf8_unicode_ci NOT NULL DEFAULT '',
`service_price` int(11) NOT NULL,
`service_date_added` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
`service_date_expire` timestamp NOT NULL DEFAULT '0000-00-00 00:00:00',
`service_time` varchar(256) COLLATE utf8_unicode_ci NOT NULL DEFAULT '0',
`service_rate` varchar(256) COLLATE utf8_unicode_ci NOT NULL DEFAULT '0',
`service_type` int(10) NOT NULL DEFAULT '1' COMMENT '1-in call, 2-out call, 3-in&out call',
`service_recomanded` int(2) NOT NULL DEFAULT '0',
`service_genre` varchar(100) COLLATE utf8_unicode_ci NOT NULL,
`service_message` text COLLATE utf8_unicode_ci NOT NULL,
PRIMARY KEY (`service_id`),
KEY `user_id` (`user_id`),
KEY `service_ICOC` (`service_ICOC`(255)),
KEY `service` (`user_id`,`service_price`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=854 ;
-- --------------------------------------------------------
--
-- Table structure for table `user`
--
CREATE TABLE IF NOT EXISTS `user` (
`user_id` int(11) NOT NULL AUTO_INCREMENT,
`user_name` varchar(256) COLLATE utf8_unicode_ci DEFAULT NULL,
`user_password` varchar(256) COLLATE utf8_unicode_ci NOT NULL,
`user_email` varchar(256) COLLATE utf8_unicode_ci DEFAULT NULL,
`user_phone` varchar(256) COLLATE utf8_unicode_ci DEFAULT NULL,
`user_address1` text COLLATE utf8_unicode_ci,
`user_address2` text COLLATE utf8_unicode_ci NOT NULL,
`user_city` varchar(256) COLLATE utf8_unicode_ci NOT NULL,
`user_state` varchar(256) COLLATE utf8_unicode_ci NOT NULL,
`user_country` varchar(256) COLLATE utf8_unicode_ci NOT NULL,
`user_company` varchar(256) COLLATE utf8_unicode_ci NOT NULL,
`user_birthday` date DEFAULT NULL,
`user_register_date` timestamp NULL DEFAULT CURRENT_TIMESTAMP,
`user_type` enum('provider','client') COLLATE utf8_unicode_ci DEFAULT NULL,
`user_description` text COLLATE utf8_unicode_ci NOT NULL,
`user_available` int(10) NOT NULL DEFAULT '1',
`verified_email` tinyint(1) NOT NULL DEFAULT '0',
`verified_facebook` tinyint(1) NOT NULL DEFAULT '0',
`verified_phone` tinyint(1) NOT NULL DEFAULT '0',
`verified_twitter` tinyint(1) NOT NULL DEFAULT '0',
`user_facebook_friends` int(11) NOT NULL DEFAULT '0',
`user_twitter_friends` int(11) NOT NULL DEFAULT '0',
`user_longitude` decimal(10,5) NOT NULL DEFAULT '0.00000',
`user_latitude` decimal(10,5) NOT NULL DEFAULT '0.00000',
`user_deleted` tinyint(4) NOT NULL DEFAULT '0',
`user_gender` int(11) NOT NULL DEFAULT '0',
`user_facebook_token` varchar(200) COLLATE utf8_unicode_ci NOT NULL,
`user_active` tinyint(4) NOT NULL DEFAULT '1',
`user_location` varchar(200) COLLATE utf8_unicode_ci NOT NULL,
`user_push_notification_token` varchar(100) COLLATE utf8_unicode_ci NOT NULL,
`user_timezone_diff` int(11) NOT NULL DEFAULT '0',
`balanced_uri` text COLLATE utf8_unicode_ci NOT NULL,
`user_reset_passwd_token` varchar(200) COLLATE utf8_unicode_ci NOT NULL,
`is_test_user` int(11) NOT NULL DEFAULT '0',
PRIMARY KEY (`user_id`),
KEY `deleted_idx` (`user_deleted`),
KEY `email_idx` (`user_email`(255))
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=426 ;
答案 0 :(得分：1)
您可以添加索引以加快查询速度。尝试添加以下索引：
service(user_id, service_price)
providerphoto(user_id, providerphoto_order)
review(user_id, review_rate)
答案 1 :(得分：1)
像这样的东西。这将返回用户的所有值，因为我在查询中未使用ORDER和LIMIT。这仅适用于该方法。
SELECT
a.user_id as id,
user_name as name,
user_phone as phone,
user_email as email,
user_address1 as address1,
user_address2 as address2,
user_city as city,
user_state as state,
user_country as country,
user_available as available,
user_location as location,
user_latitude as latitude,
user_longitude as longitude,
user_description as description,
user_company as company,
user_gender as gender,
MIN(s.service_price) as price,
s.service_recomanded as recomandad,
verified_email,
verified_facebook,
verified_phone,
verified_twitter,
pp.providerphoto_name as photo,
ROUND( AVG(r.review_rate),2) as rate,
s.service_ICOC as type
FROM
user a LEFT JOIN service s on s.user_id = a.user_id LEFT JOIN providerphoto pp on pp.user_id = a.user_id LEFT JOIN review r on r.user_id = a.user_id
WHERE a.user_type = 'provider'
AND a.user_active=1
AND a.user_deleted=0;
答案 2 :(得分：0)
我要做的第一件事就是索引user.user_type，user.user_deleted和user.user_active，让优化器快速启动一组较小的user记录来处理。
你的意思是允许service.user_id为NULL吗？这似乎是一个错误。
此外，您可能希望在正在执行ORDER BY的任何列上抛出索引。
找出此查询速度慢的最佳方法是执行EXPLAIN QUERY并分析它告诉您的内容。我们也可以为您提供帮助。