SQLite 计数汇总查询

Question

我正在尝试查询来总结每个员工一周的工作。例如，John Doe 一周总共做了 12 张票，其中 4 张是 Break/Fixes，4 张是 Enhancement，另外 4 张是未分类的。

这是我到目前为止：

SELECT (users.first_name || ' ' || users.last_name) AS Name,
  COUNT(tickets.id) AS 'Number of Tickets Closed',
  COUNT(tickets.category = 'Maintenance') AS 'Maintenance Tickets',
  COUNT(tickets.category = 'After Hours') AS 'After Hours Tickets',
  COUNT(tickets.category = 'Break Fix') AS 'Break Fix Tickets',
  COUNT(tickets.category = 'Enhancement') AS 'Enhancement Tickets',
  COUNT(tickets.category = '') AS 'Non Categorized Tickets'
FROM tickets, users
ON tickets.assigned_to=users.id
WHERE (tickets.status = 'closed') AND
  (tickets.closed_at >= '2011-07-16 00:00:00') AND
  (tickets.closed_at <= '2011-07-22 23:59:59')
GROUP BY Name;

这是一个示例结果：

约翰·杜 1 10 10 10 10 10 10

约翰·杜 2 2 2 2 2 2

约翰·杜 3 25 24 24 24 24 24

约翰·杜 4 2 2 2 2 2 2

约翰·杜 5 12 10 10 10 10 10

约翰·多伊6 7 7 7 7 7 7

这个查询并不像我预期的那样工作，因为所有列的总数都相同（关闭的票总数，以下列似乎只包含分类的。）帮助？

编辑

只是想发布功能代码：

SELECT (users.first_name || ' ' || users.last_name) AS Name,
  COUNT(tickets.id) AS 'Number of Tickets Closed',
  COUNT(case tickets.category when 'Maintenance' then 1 else null end) AS 'Maintenance Tickets',
  COUNT(case tickets.category when 'After Hours' then 1 else null end) AS 'After Hours Tickets',
  COUNT(case tickets.category when 'Break Fix' then 1 else null end) AS 'Break Fix Tickets',
  COUNT(case tickets.category when 'Enhancement' then 1 else null end) AS 'Enhancement Tickets',
  COUNT(case tickets.category when '' then 1 else null end) AS 'Non Categorized Tickets'
FROM tickets, users
ON tickets.assigned_to=users.id
WHERE (tickets.status = 'closed') AND
  (tickets.closed_at >= '2011-07-16') AND
  (tickets.closed_at <= '2011-07-22')
GROUP BY Name;

Answer 1

你可能想像这样使用 COUNT

...
    COUNT(case tickets.category when 'Maintenance' then 1 else null end),
    COUNT(case tickets.category when 'After Hours' then 1 else null end),
...