Question

我想知道是否有办法在不影响计数列的情况下过滤结果。我有订单，员工和服务表。我有一个查询，显示员工完成的服务，计算每项服务的员工数量，并计算每个服务的每位员工的价格。我想做的是仅过滤掉特定员工完成的服务，但保持员工人数相同。以下查询显示了我想要的内容，但每当我向WHERE子句添加员工ID时，员工数量显然会降至1。

SELECT R.`order_id`, R.`service_id`, S.`name` AS 'service_name', Rprice.`price` AS 'service_price', COUNT(R.`employee_id`) AS 'number_employees', ROUND(Rprice.`price` / COUNT(R.`employee_id`), 2) AS 'price_employee_service' FROM `R_services_employees_orders` R
JOIN `R_order_service_price` Rprice ON R.`order_id` = Rprice.`order_id` AND R.`service_id` = Rprice.`service_id`
JOIN `Employees` E ON R.`employee_id` = E.`id`
JOIN `Orders` O on R.`order_id` = O.`id`
JOIN `Services` S on R.`service_id` = S.`id`
WHERE NOT E.`department` = 'o' 
AND O.`completed` BETWEEN '2017-04-26' AND '2017-05-06'
GROUP BY R.`order_id`, R.`service_id`
ORDER BY R.`order_id`, R.`service_id`;

我尝试过使用子查询，但似乎无法获得正确的查询。提前谢谢。

表格结构如下

CREATE TABLE `Employees` (
  `id` varchar(3) NOT NULL DEFAULT '',
  `name` varchar(50) DEFAULT NULL,
  `department` varchar(1) DEFAULT NULL COMMENT 'Enter P R or M',
  `active` tinyint(1) DEFAULT '1',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;


CREATE TABLE `Orders` (
  `id` int(11) unsigned NOT NULL,
  `completed` datetime DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

CREATE TABLE `R_order_service_price` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `order_id` int(11) unsigned DEFAULT NULL,
  `service_id` varchar(6) DEFAULT NULL,
  `price` float DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `FK_order_price` (`order_id`),
  KEY `FK_service_price` (`service_id`),
  CONSTRAINT `FK_order_price` FOREIGN KEY (`order_id`) REFERENCES `Orders` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION,
  CONSTRAINT `FK_service_price` FOREIGN KEY (`service_id`) REFERENCES `Services` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

CREATE TABLE `R_services_employees_orders` (
  `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
  `order_id` int(11) unsigned DEFAULT NULL,
  `employee_id` varchar(3) DEFAULT NULL,
  `service_id` varchar(6) DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `FK_order` (`order_id`),
  KEY `FK_service` (`service_id`),
  KEY `FK_employee` (`employee_id`),
  CONSTRAINT `FK_employee` FOREIGN KEY (`employee_id`) REFERENCES `Employees` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION,
  CONSTRAINT `FK_order` FOREIGN KEY (`order_id`) REFERENCES `Orders` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION,
  CONSTRAINT `FK_service` FOREIGN KEY (`service_id`) REFERENCES `Services` (`id`) ON DELETE NO ACTION ON UPDATE NO ACTION
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Sample result from the above query

Answer 1

您可以在选择中使用CASE语句，例如：

width=n

您可以通过这种方式汇总任何员工特定的衡量标准，以便在正常计算中保持整体汇总。

使用嵌套的SQL语句进行过滤而不影响计数

1 个答案: