计算已登录用户打开或保留的任务数

Question

我想创建Sql脚本，以查看仅为已分配的登录用户打开或暂停的任务数 任务 结果 HelloWorld1（0） HelloWorld2（2） HelloWorld3（1） HelloWorld4（5）

SELECT Projects.projectID,
    Projects.projectName + ' ' + '(' + CONVERT(NVARCHAR, COUNT(Projects_tasks.taskID)) + ')' AS Project
  FROM Projects
  LEFT JOIN Projects_tasks ON Projects.projectID = Projects_tasks.projectID
 INNER JOIN Users_projects ON Projects.projectID = Users_projects.projectID
 INNER JOIN Tasks ON Projects_tasks.taskID = Tasks.taskID
 INNER JOIN Users_Tasks ON Tasks.taskID = Users_Tasks.TaskID
 WHERE Users_Tasks.userID = @userID
   AND Tasks.status = 'Open'
   AND Tasks.status = 'Onhold'
 GROUP BY Users_projects.userID,
          Projects.projectName,
          Projects.projectID,
          Users_Tasks.userID

Answer 1

你有：

AND (Tasks.status = 'Open' AND Tasks.status = 'Onhold') 

哪个不可能是真的;任务不能同时具有两个值。你想要：

AND (Tasks.status = 'Open' OR Tasks.status = 'Onhold') 

更好的是，使用IN：

AND (Tasks.status IN ('Open', 'Onhold') )

Answer 2

没有行可以匹配：

(Tasks.status = 'Open' AND Tasks.status = 'Onhold')

尝试

(Tasks.status = 'Open' OR Tasks.status = 'Onhold')

或者：

Tasks.status in ('Open', 'Onhold')

Answer 3

如前所述，AND子句无法满足，因为Task.Status只能打开或 OnHold 。使用以下代码：

SELECT Projects.projectID,
    Projects.projectName + ' ' + '(' + CONVERT(NVARCHAR, COUNT(Projects_tasks.taskID)) + ')' AS Project
  FROM Projects
  LEFT JOIN Projects_tasks ON Projects.projectID = Projects_tasks.projectID
 INNER JOIN Users_projects ON Projects.projectID = Users_projects.projectID
 INNER JOIN Tasks ON Projects_tasks.taskID = Tasks.taskID
 INNER JOIN Users_Tasks ON Tasks.taskID = Users_Tasks.TaskID
 WHERE Users_Tasks.userID = @userID
   AND (Tasks.status = 'Open' OR Tasks.status = 'Onhold')
 --also this code can be used: 
 --AND Tasks.status in ('Open', 'Onhold')
 GROUP BY Users_projects.userID,
          Projects.projectName,
          Projects.projectID,
          Users_Tasks.userID