Returning a single row on an INNER JOIN

I would like to return the first row only from an inner join. I have two tables:

Rows in TABLE_D and TABLE_E can have identical creation dates so I am first getting the MAX(creationdate) and then then MAX(id) from this set. Here's my complete query:

SELECT
a.id as A_ID,
b.id as B_ID,
c.id as C_ID,
d.id as D_ID,
e.id as E_ID,
d.CREATIONDATE,
a.REFNUMBER,
a.DATECREATED,
a.INFO,
e.COST,
FROM 
TABLE_A a
INNER JOIN TABLE_B b ON (b.id = a.id)
INNER JOIN TABLE_C c ON (c.id = b.id)
INNER JOIN TABLE_D d ON
(
   c.i =
   (
      select
      d.id
      FROM TABLE_D
      WHERE TABLE_D.id = c.id
      AND TABLE_D.id =
      (
         select
         max(id)
         from TABLE_D t1
         where c_id = c.id
         and CREATIONDATE =
         (
            select
            max(CREATIONDATE)
            from TABLE_D t2
            where t2.c_id = t1.c_id
         )
      )
   ) 
)

INNER JOIN TABLE_E e ON
(
   d.i =
   (
      select
      e.d_id
      from TABLE_E
      where d_id = d.id
      AND id =
      (
         select
         max(id)
         from e t1
         where e.d_id = d.id
         and CREATIONDATE =
         (
            select
            max(CREATIONDATE)
            from TABLE_E t2
            where t2.d_id = t1.d开发者_开发问答_id
         )
      )
   )
)

My subquery to get all rows with a max creationdate and from that the max id works fine when I call it on it's own but when I add it to an INNER JOIN (see above) I am getting a row for each matching row in table D and table E. What I want is one row per TABLE_A.id showing only the latest row from TABLE_D associated with TABLE_C and the latest from TABLE_E associated with TABLE_D.

For example, the id's in my result set look like this at the moment:

--------------------------------------------------------------------------
A_ID            B_ID            C_ID            D_ID            E_ID
--------------------------------------------------------------------------
1               101             201             301             401
1               101             201             301             402    
1               101             201             301             403    
1               101             201             302             404
1               101             201             302             405    
1               101             201             302             406    

what I need is this:

--------------------------------------------------------------------------
A_ID            B_ID            C_ID            D_ID            E_ID
--------------------------------------------------------------------------
1               101             201             302             406

Thanks in advance for your help.

Use the analytical function ROW_NUMBER() which is available in oracle11g

SELECT *
FROM 
(
SELECT
    a.id as A_ID,b.id as B_ID,c.id as C_ID,d.id as D_ID,e.id as E_ID,
    d.CREATIONDATE,a.REFNUMBER,a.DATECREATED,a.INFO,e.COST,
    row_number() over (
        partition by a.id, b.id, c.id
        order by d.CREATIONDATE DESC, d.id desc, e.CREATIONDATE DESC, e.id desc) RN
FROM TABLE_A a
INNER JOIN TABLE_B b ON (b.id = a.id)
INNER JOIN TABLE_C c ON (c.id = b.id)
INNER JOIN TABLE_D d ON d.c_id = c.id
INNER JOIN TABLE_E e ON e.d_id = d.id
) N
WHERE RN = 1

Just make sure the PARTITION and ORDER BY clauses are correct

partition by a.id, b.id, c.id
    => start numbering from 1 again when any one of these changes
order by d.CREATIONDATE DESC, d.id desc, e.CREATIONDATE DESC, e.id desc)
    => number the rows in this order

What I would do is move the inner query to select clause. I will just keep direct mapping while filtering

SELECT
a.id as A_ID,
b.id as B_ID,
c.id as C_ID,
(select max(d.id) from d where d.id =c.id) as d_id)
FROM 
TABLE_A a
INNER JOIN TABLE_B b ON (b.id = a.id)
INNER JOIN TABLE_C c ON (c.id = b.id)

You could insert your query in a subquery and use a WHERE ROWNUM<2 filter.

SELECT * FROM
(/* Your SQL */)
WHERE ROWNUM < 2

Maybe this would work for you?

SELECT TOP 1
a.id as A_ID,
b.id as B_ID,
c.id as C_ID,
d.id as D_ID,
e.id as E_ID,
d.CREATIONDATE,
a.REFNUMBER,
a.DATECREATED,
a.INFO,
e.COST,
FROM 
TABLE_A a
INNER JOIN TABLE_B b ON (b.id = a.id)
INNER JOIN TABLE_C c ON (c.id = b.id)
INNER JOIN TABLE_D d ON (c.i = d.id)
INNER JOIN TABLE_E e ON ( d.i = e.id )
ORDER BY d.creationdate DESC, e.creationdate DESC