How to get PARENT_TASK_ID for tasks in pa_proj_elements table,

 Hi ,

I new to Projects module. I am trying to create a report in which i need PARENT_TASK_ID to get the parent tasks information for child tasks.

I can find the parent and child task relations in pa_tasks table but not all the tasks are sitting in these pa_tasks table . so i am using pa_proj_elements table which has all tasks present in it.

what i came to know is only the FINANCIAL TASKS are sitting in the pa_tasks table. where can i get the parent and child task relations for non FINANCIAL TASKS that are present in pa_proj_elements table?