SQL stored procedure

I have a table
TableA
id    parent_id   Desc
a
b
c            e
d
e
f             a
g

I want to filter out all the results from this table which just show b,c,d,f,g
since e and a are parents I do not want to select the.

I have a function which checks for this

wether it is a parent-- 0 = false, 1 = true
-- =============================================
Alter FUNCTION  isParent
(
@id char(15)
)
RETURNS  tinyint
AS
BEGIN
      
      -- Return the result of the function
      RETURN  (
            CASE WHEN (SELECT COUNT(id) from tableA where parent_id = @id) = 0
                        THEN 0
                        ELSE 1
                  END      
                  )
END

This function is called from a stored procedure which returns a table variable.

It all works fine. When we have a few records now we have 60000 records and everytime to check if it is a parent I am taking one record and going through 60000 records. The procedure takes 40 minutes to run.

I thought would create a temp table and check the ISParent function against records which have parents_Id but if I create a temp table in stored procedure my function cannot access it.

If I create a temp table in IsParent I get cannot create temp table in a function.

I need help in taking  the IsParent function and writing it in form of a SQL statement such that I can access the temp table in the stored procedure and donot use the IsPArent function or any other suggestions.

Thanks YRKSStart Free Trial