mysql PHP join - 语法问题

Question

I am trying to join 3 tables but I keep getting an error with my query. I am not sure what I am doing wrong. I must be doing something incorrect with my syntax but I am not quite sure what is wrong.

SELECT project_timecard_tasks.DateTime,
        project_timecard_tasks.Total_Hours,
        project_timecard_tasks.User_ID,
        project_timecard_tasks.Task_ID,
        project_timecard_tasks.Project_ID,
        users.User_ID,
        users.FirstName,
        users.LastName,
        tasks.id,
        tasks.taskName

 FROM project_timecard_tasks

 JOIN project_timecard_tasks ON project_timecard_tasks.User_ID = users.User_ID 
 AND project_timecard_tasks.Task_ID = tasks.id

 WHERE project_timecard_tasks.Project_ID = '$jobNumber'

Answer 1

Your JOIN statement is a little wonky. Try this:

SELECT project_timecard_tasks.DateTime,
        project_timecard_tasks.Total_Hours,
        project_timecard_tasks.User_ID,
        project_timecard_tasks.Task_ID,
        project_timecard_tasks.Project_ID,
        users.User_ID,
        users.FirstName,
        users.LastName,
        tasks.id,
        tasks.taskName

 FROM project_timecard_tasks

 JOIN users ON project_timecard_tasks.User_ID = users.User_ID 
 JOIN tasks ON project_timecard_tasks.Task_ID = tasks.id

 WHERE project_timecard_tasks.Project_ID = '$jobNumber'