Question

我有以下查询。在这里，我有，没有案例。是访问，但其他部分不起作用。请看一下。

SELECT SalesChannel.name , count(Transaction.category_id) as count, (case when (Transaction.no_of_units > 0 and Transaction.mop > 0) THEN 'yes' ELSE 'No' END) AS Is_Present from outlets Outlet inner join transactions Transaction on Outlet.id = Transaction.outlet_id inner join sale_channels SalesChannel on SalesChannel.id = Outlet.sale_channel_id group by SalesChannel.name

输出应如下

   KU      Electrical  
Yes   6       2  
No    1       2

6是KU的计数器，Yes表示存在，类似No不存在KU

select SalesChannel.name , 
Transaction.category_id, 
count(Transaction.category_id) as count,   
from outlets Outlet inner join transactions Transaction on Outlet.id = Transaction.outlet_id inner join sale_channels SalesChannel on SalesChannel.id = Outlet.sale_channel_id group by SalesChannel.name

下面是我使用的三个表交易



CREATE TABLE IF NOT EXISTS `transactions` (
`id` int(11) NOT NULL,
  `zone_id` int(11) NOT NULL,
  `state_id` int(11) NOT NULL,
  `city_id` int(11) NOT NULL,
  `category_id` int(11) NOT NULL,
  `sub_category_id` int(11) NOT NULL,
  `brand_id` int(11) NOT NULL,
  `model_id` int(11) NOT NULL,
  `outlet_id` int(11) NOT NULL,
  `no_of_units` int(11) NOT NULL,
  `mop` decimal(10,2) NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=latin1;

--
-- Dumping data for table `transactions`
--

INSERT INTO `transactions` (`id`, `zone_id`, `state_id`, `city_id`, `category_id`, `sub_category_id`, `brand_id`, `model_id`, `outlet_id`, `no_of_units`, `mop`) VALUES
(1, 2, 2, 2, 2, 1, 1, 1, 1, 3, '6.00'),
(2, 2, 2, 2, 2, 1, 1, 1, 1, 3, '6.00'),
(3, 1, 1, 1, 1, 1, 1, 1, 1, 4, '2.00'),
(4, 2, 2, 2, 1, 1, 1, 1, 2, 4, '2.00');

CREATE TABLE IF NOT EXISTS `transactions` ( `id` int(11) NOT NULL, `zone_id` int(11) NOT NULL, `state_id` int(11) NOT NULL, `city_id` int(11) NOT NULL, `category_id` int(11) NOT NULL, `sub_category_id` int(11) NOT NULL, `brand_id` int(11) NOT NULL, `model_id` int(11) NOT NULL, `outlet_id` int(11) NOT NULL, `no_of_units` int(11) NOT NULL, `mop` decimal(10,2) NOT NULL ) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=latin1; -- -- Dumping data for table `transactions` -- INSERT INTO `transactions` (`id`, `zone_id`, `state_id`, `city_id`, `category_id`, `sub_category_id`, `brand_id`, `model_id`, `outlet_id`, `no_of_units`, `mop`) VALUES (1, 2, 2, 2, 2, 1, 1, 1, 1, 3, '6.00'), (2, 2, 2, 2, 2, 1, 1, 1, 1, 3, '6.00'), (3, 1, 1, 1, 1, 1, 1, 1, 1, 4, '2.00'), (4, 2, 2, 2, 1, 1, 1, 1, 2, 4, '2.00'); 2.outlets

CREATE TABLE IF NOT EXISTS `outlets` (
`id` int(11) NOT NULL,
  `outlet_code` varchar(255) NOT NULL,
  `name` varchar(255) NOT NULL,
  `zone_id` int(11) NOT NULL,
  `state_id` int(11) NOT NULL,
  `city_id` int(11) NOT NULL,
  `sale_channel_id` int(11) NOT NULL,
  `is_active` tinyint(1) NOT NULL,
  `created` datetime NOT NULL,
  `modified` datetime NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=latin1;

--
-- Dumping data for table `outlets`
--

INSERT INTO `outlets` (`id`, `outlet_code`, `name`, `zone_id`, `state_id`, `city_id`, `sale_channel_id`, `is_active`, `created`, `modified`) VALUES
(1, '1508', 'Ashok electricals', 2, 2, 2, 1, 1, '2016-10-03 00:00:00', '2016-10-03 00:00:00'),
(2, '1233', 'vinayak electricals', 1, 1, 1, 2, 1, '2016-10-04 00:00:00', '2016-10-04 00:00:00');

3. sale_chennals

CREATE TABLE IF NOT EXISTS `outlets` (
`id` int(11) NOT NULL,
  `outlet_code` varchar(255) NOT NULL,
  `name` varchar(255) NOT NULL,
  `zone_id` int(11) NOT NULL,
  `state_id` int(11) NOT NULL,
  `city_id` int(11) NOT NULL,
  `sale_channel_id` int(11) NOT NULL,
  `is_active` tinyint(1) NOT NULL,
  `created` datetime NOT NULL,
  `modified` datetime NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=latin1;

--
-- Dumping data for table `outlets`
--

INSERT INTO `outlets` (`id`, `outlet_code`, `name`, `zone_id`, `state_id`, `city_id`, `sale_channel_id`, `is_active`, `created`, `modified`) VALUES
(1, '1508', 'Ashok electricals', 2, 2, 2, 1, 1, '2016-10-03 00:00:00', '2016-10-03 00:00:00'),
(2, '1233', 'vinayak electricals', 1, 1, 1, 2, 1, '2016-10-04 00:00:00', '2016-10-04 00:00:00');

Answer 1

表中没有与else条件匹配的数据。您的条件是＆＃34; Transaction.no_of_units＆gt; 0 AND Transaction.mop＆gt; 0＆＃34;两个字段的表值不匹配，大于0。

否则，其他条件正常。

Answer 2

您正在聚合数据，以便为每个SalesChannel.name获取一行。可能会有一些交易记录导致“是”＆＃39;和其他人在＆＃39; No＆＃39;对于SalesChannel.name，那么Is_Present应该是什么？

您的查询的另一个问题是销售渠道位于表格中。目前有两个，但有时可能有三个或四个或几千个。 SQL查询不会生成具有可变列数的结果。必须事先知道列。所以可能的结果可能如下所示：

Name          Yes   No
KU            6     1  
Electrical    2     2

因为您知道无论有多少频道，您都希望它为“是”或“否”。

查询：

select 
  sc.name,
  count(case when t.no_of_units > 0 and t.mop > 0 then 1 end) as yes,
  count(case when t.no_of_units <= 0 or t.mop <= 0 then 1 end) as no
from sale_channels sc
join outlet o on o.sale_channel_id = sc.id
join transactions t on t.outlet_id = o.id;

否则没有在mysql Query

2 个答案: