mysql - 相同的 MySQL 查询在同一服务器上返回不同的结果

Question

我正在运行以下查询。有时它返回大约 100 条记录，正如预期的那样，其他时候它只返回一条记录，其中所有连接字段的值都为 NULL。此外，explain 几乎每次都会返回不同的结果。

这里是查询:

EXPLAIN
SELECT
`fieldreps`.`user_id` AS `fieldreps.user_id`,
 `fieldreps`.`availability_id` AS `fieldreps.availability_id`,
 `fieldreps`.`applicant_type` AS `fieldreps.applicant_type`,
 `fieldreps`.`license_number` AS `fieldreps.license_number`,
 `fieldreps`.`license_exp` AS `fieldreps.license_exp`,
 `fieldreps`.`license_state` AS `fieldreps.license_state`,
 `fieldreps`.`car` AS `fieldreps.car`,
 `fieldreps`.`authorized_worker` AS `fieldreps.authorized_worker`,
 `fieldreps`.`restrictions` AS `fieldreps.restrictions`,
 `fieldreps`.`night` AS `fieldreps.night`,
 `fieldreps`.`day` AS `fieldreps.day`,
 `fieldreps`.`longer` AS `fieldreps.longer`,
 `fieldreps`.`commitment` AS `fieldreps.commitment`,
 `fieldreps`.`travel_metro` AS `fieldreps.travel_metro`,
 `fieldreps`.`travel_states` AS `fieldreps.travel_states`,
 `fieldreps`.`big_employee` AS `fieldreps.big_employee`,
 `fieldreps`.`employed` AS `fieldreps.employed`,
 `fieldreps`.`retail` AS `fieldreps.retail`,
 `fieldreps`.`status` AS `fieldreps.status`,
 `fieldreps`.`start` AS `fieldreps.start`,
 `fieldreps`.`sales` AS `fieldreps.sales`,
 `fieldreps`.`study` AS `fieldreps.study`,
 `fieldreps`.`relevant` AS `fieldreps.relevant`,
 `fieldreps`.`experience` AS `fieldreps.experience`,
 `fieldreps`.`claims` AS `fieldreps.claims`,
 `fieldreps`.`education` AS `fieldreps.education`,
 `fieldreps`.`degree_details` AS `fieldreps.degree_details`,
 `fieldreps`.`degree_institution` AS `fieldreps.degree_institution`,
 `fieldreps`.`other_training` AS `fieldreps.other_training`,
 `fieldreps`.`jobs` AS `fieldreps.jobs`,
 `fieldreps`.`current_training` AS `fieldreps.current_training`,
 `fieldreps`.`interested` AS `fieldreps.interested`,
 `fieldreps`.`achievements` AS `fieldreps.achievements`,
 `fieldreps`.`passions` AS `fieldreps.passions`,
 `fieldreps`.`ambitions` AS `fieldreps.ambitions`,
 `fieldreps`.`max_travel_time` AS `fieldreps.max_travel_time`,
 `fieldreps`.`creation_time` AS `fieldreps.creation_time`,
 `fieldreps`.`resume` AS `fieldreps.resume`,
 `users`.`user_id` AS `users.user_id`,
 `users`.`email` AS `users.email`,
 `users`.`name` AS `users.name`,
 `users`.`password` AS `users.password`,
 `users`.`given_name` AS `users.given_name`,
 `users`.`title` AS `users.title`,
 `users`.`nationality` AS `users.nationality`,
 `tasks`.`task_id` AS `tasks.task_id`,
 `tasks`.`recurrence_id` AS `tasks.recurrence_id`,
 `tasks`.`parent_id` AS `tasks.parent_id`,
 `tasks`.`user_id` AS `tasks.user_id`,
 `tasks`.`campaign_id` AS `tasks.campaign_id`,
 `tasks`.`location_id` AS `tasks.location_id`,
 `tasks`.`title` AS `tasks.title`,
 `tasks`.`description` AS `tasks.description`,
 `tasks`.`earliest_start` AS `tasks.earliest_start`,
 `tasks`.`deadline` AS `tasks.deadline`,
 `tasks`.`km_estimate` AS `tasks.km_estimate`,
 `tasks`.`estimate` AS `tasks.estimate`,
 `datapoints`.`datapoint_id` AS `datapoints.datapoint_id`,
 `datapoints`.`task_id` AS `datapoints.task_id`,
 `datapoints`.`datatype_id` AS `datapoints.datatype_id`,
 `datapoints`.`value` AS `datapoints.value`,
 `datapoints`.`product_id` AS `datapoints.product_id`,
 `datapoints`.`recorded` AS `datapoints.recorded`,
 `datatypes`.`datatype_id` AS `datatypes.datatype_id`,
 `datatypes`.`datatype_template_id` AS `datatypes.datatype_template_id`,
 `datatypes`.`client_id` AS `datatypes.client_id`,
 `datatypes`.`name` AS `datatypes.name`,
 `datatypes`.`description` AS `datatypes.description`,
 `datatypes`.`options` AS `datatypes.options`,
 `locations`.`location_id` AS `locations.location_id`,
 `locations`.`retailer_group_id` AS `locations.retailer_group_id`,
 `locations`.`latitude` AS `locations.latitude`,
 `locations`.`longitude` AS `locations.longitude`,
 `locations`.`name` AS `locations.name`,
 `locations`.`address` AS `locations.address`,
 `locations`.`city` AS `locations.city`,
 `locations`.`state` AS `locations.state`,
 `locations`.`postal` AS `locations.postal`,
 `locations`.`phone` AS `locations.phone`,
 `locations`.`suburb` AS `locations.suburb`,
 `locations`.`country` AS `locations.country`,
 `locations`.`region` AS `locations.region`,
 `locations`.`coverage` AS `locations.coverage`,
 `locations`.`store_number` AS `locations.store_number`,
 `locations`.`store_type` AS `locations.store_type`

 FROM `fieldreps` AS `fieldreps`

 LEFT JOIN `users` ON (`fieldreps`.`user_id` = `users`.`user_id`)
 LEFT JOIN `tasks` ON (`fieldreps`.`user_id` = `tasks`.`user_id`)
 LEFT JOIN `datapoints` ON (`tasks`.`task_id` = `datapoints`.`task_id`)
 LEFT JOIN `datatypes` ON (`datapoints`.`datatype_id` = `datatypes`.`datatype_id`)
 LEFT JOIN `locations` ON (`tasks`.`location_id` = `locations`.`location_id`)

 WHERE `fieldreps`.`user_id` LIKE '5f5dc29c-832e-5646-9dc2-46d774bfb1ec'

我在 phpMyAdmin 中运行查询。数据库托管在 xeround.com 上(这可能是他们配置中的错误吗？)

我被难住了。我不确定从这里到哪里去。

提前致谢!

更新:

这是来自 phpMyAdmin 的转储:

-- phpMyAdmin SQL Dump
-- version 3.4.3.2
-- http://www.phpmyadmin.net
--
-- Generation Time: Jan 07, 2012 at 08:20 PM
-- Server version: 5.1.42
-- PHP Version: 5.3.1

SET SQL_MODE="NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";


/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8 */;

--
-- Database: `big_development`
--

-- --------------------------------------------------------

--
-- Table structure for table `datapoints`
--

CREATE TABLE IF NOT EXISTS `datapoints` (
  `datapoint_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `task_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `datatype_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `value` text COLLATE utf8_bin,
  `product_id` varchar(36) COLLATE utf8_bin DEFAULT NULL,
  `recorded` text COLLATE utf8_bin,
  PRIMARY KEY (`datapoint_id`),
  KEY `task_id` (`task_id`),
  KEY `datatype_id` (`datatype_id`),
  KEY `product_id` (`product_id`)
) ENGINE=Xeround DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

-- --------------------------------------------------------

--
-- Table structure for table `datatypes`
--

CREATE TABLE IF NOT EXISTS `datatypes` (
  `datatype_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `datatype_template_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `client_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `name` text COLLATE utf8_bin,
  `description` text COLLATE utf8_bin,
  `options` text COLLATE utf8_bin,
  PRIMARY KEY (`datatype_id`),
  KEY `datatype_template_id` (`datatype_template_id`),
  KEY `client_id` (`client_id`)
) ENGINE=Xeround DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

-- --------------------------------------------------------

--
-- Table structure for table `fieldreps`
--

CREATE TABLE IF NOT EXISTS `fieldreps` (
  `user_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `availability_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `applicant_type` text COLLATE utf8_bin NOT NULL,
  `license_number` text COLLATE utf8_bin NOT NULL,
  `license_exp` text COLLATE utf8_bin,
  `license_state` text COLLATE utf8_bin,
  `car` text COLLATE utf8_bin NOT NULL,
  `authorized_worker` text COLLATE utf8_bin NOT NULL,
  `restrictions` text COLLATE utf8_bin NOT NULL,
  `night` text COLLATE utf8_bin NOT NULL,
  `day` text COLLATE utf8_bin NOT NULL,
  `longer` text COLLATE utf8_bin NOT NULL,
  `commitment` text COLLATE utf8_bin NOT NULL,
  `travel_metro` text COLLATE utf8_bin NOT NULL,
  `travel_states` text COLLATE utf8_bin NOT NULL,
  `big_employee` text COLLATE utf8_bin NOT NULL,
  `employed` text COLLATE utf8_bin NOT NULL,
  `retail` text COLLATE utf8_bin NOT NULL,
  `status` text COLLATE utf8_bin NOT NULL,
  `start` text COLLATE utf8_bin,
  `sales` text COLLATE utf8_bin NOT NULL,
  `study` text COLLATE utf8_bin NOT NULL,
  `relevant` text COLLATE utf8_bin NOT NULL,
  `experience` text COLLATE utf8_bin NOT NULL,
  `claims` text COLLATE utf8_bin NOT NULL,
  `education` text COLLATE utf8_bin NOT NULL,
  `degree_details` text COLLATE utf8_bin NOT NULL,
  `degree_institution` text COLLATE utf8_bin NOT NULL,
  `other_training` text COLLATE utf8_bin NOT NULL,
  `jobs` text COLLATE utf8_bin NOT NULL,
      `current_training` text COLLATE utf8_bin NOT NULL,
  `interested` text COLLATE utf8_bin NOT NULL,
  `achievements` text COLLATE utf8_bin NOT NULL,
  `passions` text COLLATE utf8_bin NOT NULL,
  `ambitions` text COLLATE utf8_bin NOT NULL,
  `max_travel_time` text COLLATE utf8_bin NOT NULL,
  `creation_time` text COLLATE utf8_bin,
  `resume` text COLLATE utf8_bin NOT NULL,
  PRIMARY KEY (`user_id`),
  KEY `availability_id` (`availability_id`)
) ENGINE=Xeround DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

-- --------------------------------------------------------

--
-- Table structure for table `locations`
--

CREATE TABLE IF NOT EXISTS `locations` (
  `location_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `retailer_group_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `latitude` text COLLATE utf8_bin,
  `longitude` text COLLATE utf8_bin,
  `name` text COLLATE utf8_bin,
  `address` text COLLATE utf8_bin,
  `city` text COLLATE utf8_bin,
  `state` text COLLATE utf8_bin,
  `postal` text COLLATE utf8_bin,
  `phone` text COLLATE utf8_bin,
  `suburb` text COLLATE utf8_bin,
  `country` text COLLATE utf8_bin,
  `region` text COLLATE utf8_bin,
  `coverage` tinyint(1) DEFAULT NULL,
  `store_number` text COLLATE utf8_bin,
  `store_type` text COLLATE utf8_bin,
  PRIMARY KEY (`location_id`),
  KEY `retailer_group_id` (`retailer_group_id`)
) ENGINE=Xeround DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

-- --------------------------------------------------------

--
-- Table structure for table `tasks`
--

CREATE TABLE IF NOT EXISTS `tasks` (
  `task_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `recurrence_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `parent_id` varchar(36) COLLATE utf8_bin DEFAULT NULL,
  `user_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `campaign_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `location_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `title` text COLLATE utf8_bin,
  `description` text COLLATE utf8_bin,
  `earliest_start` text COLLATE utf8_bin,
  `deadline` text COLLATE utf8_bin,
  `km_estimate` text COLLATE utf8_bin,
  `estimate` int(11) DEFAULT NULL,
  PRIMARY KEY (`task_id`),
  KEY `campaign_id` (`campaign_id`),
  KEY `location_id` (`location_id`),
  KEY `user_id` (`user_id`),
  KEY `parent_id` (`parent_id`),
  KEY `recurrence_id` (`recurrence_id`)
) ENGINE=Xeround DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

-- --------------------------------------------------------

--
-- Table structure for table `users`
--

CREATE TABLE IF NOT EXISTS `users` (
  `user_id` varchar(36) COLLATE utf8_bin NOT NULL,
  `email` varchar(255) COLLATE utf8_bin NOT NULL,
  `name` text COLLATE utf8_bin,
  `password` varchar(255) COLLATE utf8_bin NOT NULL,
  `given_name` text COLLATE utf8_bin,
  `title` text COLLATE utf8_bin NOT NULL,
  `nationality` text COLLATE utf8_bin,
  PRIMARY KEY (`user_id`),
  KEY `user_id` (`user_id`)
) ENGINE=Xeround DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;

编辑:

如果我删除除用户以外的所有表的连接，查询每次都有效。但是，一旦我添加任务连接，它就会中断。例如，此查询以与我发布的第一个查询相同的方式中断它:

SELECT
`fieldreps`.`user_id` AS `fieldreps.user_id`,
 `fieldreps`.`availability_id` AS `fieldreps.availability_id`,
 `fieldreps`.`applicant_type` AS `fieldreps.applicant_type`,
 `fieldreps`.`license_number` AS `fieldreps.license_number`,
 `fieldreps`.`license_exp` AS `fieldreps.license_exp`,
 `fieldreps`.`license_state` AS `fieldreps.license_state`,
 `fieldreps`.`car` AS `fieldreps.car`,
 `fieldreps`.`authorized_worker` AS `fieldreps.authorized_worker`,
 `fieldreps`.`restrictions` AS `fieldreps.restrictions`,
 `fieldreps`.`night` AS `fieldreps.night`,
 `fieldreps`.`day` AS `fieldreps.day`,
 `fieldreps`.`longer` AS `fieldreps.longer`,
 `fieldreps`.`commitment` AS `fieldreps.commitment`,
 `fieldreps`.`travel_metro` AS `fieldreps.travel_metro`,
 `fieldreps`.`travel_states` AS `fieldreps.travel_states`,
 `fieldreps`.`big_employee` AS `fieldreps.big_employee`,
 `fieldreps`.`employed` AS `fieldreps.employed`,
 `fieldreps`.`retail` AS `fieldreps.retail`,
 `fieldreps`.`status` AS `fieldreps.status`,
 `fieldreps`.`start` AS `fieldreps.start`,
 `fieldreps`.`sales` AS `fieldreps.sales`,
 `fieldreps`.`study` AS `fieldreps.study`,
 `fieldreps`.`relevant` AS `fieldreps.relevant`,
 `fieldreps`.`experience` AS `fieldreps.experience`,
 `fieldreps`.`claims` AS `fieldreps.claims`,
 `fieldreps`.`education` AS `fieldreps.education`,
 `fieldreps`.`degree_details` AS `fieldreps.degree_details`,
 `fieldreps`.`degree_institution` AS `fieldreps.degree_institution`,
 `fieldreps`.`other_training` AS `fieldreps.other_training`,
 `fieldreps`.`jobs` AS `fieldreps.jobs`,
 `fieldreps`.`current_training` AS `fieldreps.current_training`,
 `fieldreps`.`interested` AS `fieldreps.interested`,
 `fieldreps`.`achievements` AS `fieldreps.achievements`,
 `fieldreps`.`passions` AS `fieldreps.passions`,
 `fieldreps`.`ambitions` AS `fieldreps.ambitions`,
 `fieldreps`.`max_travel_time` AS `fieldreps.max_travel_time`,
 `fieldreps`.`creation_time` AS `fieldreps.creation_time`,
 `fieldreps`.`resume` AS `fieldreps.resume`,
 `users`.`user_id` AS `users.user_id`,
     `users`.`email` AS `users.email`,
 `users`.`name` AS `users.name`,
 `users`.`password` AS `users.password`,
 `users`.`given_name` AS `users.given_name`,
 `users`.`title` AS `users.title`,
 `users`.`nationality` AS `users.nationality`,
 `tasks`.`task_id` AS `tasks.task_id`,
 `tasks`.`recurrence_id` AS `tasks.recurrence_id`,
 `tasks`.`parent_id` AS `tasks.parent_id`,
 `tasks`.`user_id` AS `tasks.user_id`,
 `tasks`.`campaign_id` AS `tasks.campaign_id`,
 `tasks`.`location_id` AS `tasks.location_id`,
 `tasks`.`title` AS `tasks.title`,
 `tasks`.`description` AS `tasks.description`,
 `tasks`.`earliest_start` AS `tasks.earliest_start`,
 `tasks`.`deadline` AS `tasks.deadline`,
 `tasks`.`km_estimate` AS `tasks.km_estimate`,
 `tasks`.`estimate` AS `tasks.estimate`

 FROM `fieldreps` AS `fieldreps`

 LEFT JOIN `users` ON (`fieldreps`.`user_id` = `users`.`user_id`)
 LEFT JOIN `tasks` ON (`fieldreps`.`user_id` = `tasks`.`user_id`)

 WHERE `fieldreps`.`user_id` LIKE '5f5dc29c-832e-5646-9dc2-46d774bfb1ec'

Answer 1

连接和数据库整理不同。