Select with condition and check

This is my table:

project_id | task_id | task_name | task_status |
  ---------+---------+-----------+-------------+
      1           12     foo       complete
      2           13     foo       complete
      3         1210     bar       complete
      4         1211     bar         none
      5         1212     xyz         none
      6         1213     zyz         none

I want create query where I can select only tasks_name where task_status “complete” for both task_id. For example one task which name foo have two task_id such as 12 and 13 and both of them have task_status complete. In contrast task with name bar have only one task_id “completed”, so its fall for my condition. I expect get table like this:

   project_id | task_id | task_name | task_status |
     ---------+---------+-----------+-------------+
         1           12     foo       complete
         2           13     foo       complete

How I can select, check and return where task_name is same for each task_id and both of them have task_status completed

Answer

It is much easier to do this using min, max and a subquery.

Select *
From Tbl
Where task_name In (Select task_name
                    From Tbl
                    Group by task_name
                    Having Min(task_status)=Max(task_status)                
                           And Max(task_status)='complete')

Data output:

project_id | task_id | task_name | task_status                         
___________|_________|___________|____________
         1 |      12 | foo       | complete    
         2 |      13 | foo       | complete