How do I limit the number of rows returned by an Oracle query after ordering?

Is there a way to make an Oracle query behave like it contains a MySQL limit clause?
In MySQL, I can do this:
select * 
from sometable
order by name
limit 20,10
to get the 21st to the 30th rows (skip the first 20, give the next 10). The rows are selected after the order by, so it really starts on the 20th name alphabetically.
In Oracle, the only thing people mention is the rownum pseudo-column, but it is evaluated before order by, which means this:
select * 
from sometable
where rownum <= 10
order by name
will return a random set of ten rows ordered by name, which is not usually what I want. It also doesn't allow for specifying an offset.

Answer :

tarting from Oracle 12c R1 (12.1), there is a row limiting clause. It does not use familiar LIMITsyntax, but it can do the job better with more options. You can find the full syntax here.
To answer the original question, here's the query:
SELECT * 
FROM   sometable
ORDER BY name
OFFSET 20 ROWS FETCH NEXT 10 ROWS ONLY;
(For earlier Oracle versions, please refer to other answers in this question)

Examples:

Following examples were quoted from linked page, in the hope of preventing link rot.

Setup

CREATE TABLE rownum_order_test (
  val  NUMBER
);

INSERT ALL
  INTO rownum_order_test
SELECT level
FROM   dual
CONNECT BY level <= 10;

COMMIT;

What's in the table?

SELECT val
FROM   rownum_order_test
ORDER BY val;

       VAL
----------
         1
         1
         2
         2
         3
         3
         4
         4
         5
         5
         6
         6
         7
         7
         8
         8
         9
         9
        10
        10

20 rows selected.

Get first N rows

SELECT val
FROM   rownum_order_test
ORDER BY val DESC
FETCH FIRST 5 ROWS ONLY;

       VAL
----------
        10
        10
         9
         9
         8

5 rows selected.

Get first N rows, if Nth row has ties, get all the tied rows

SELECT val
FROM   rownum_order_test
ORDER BY val DESC
FETCH FIRST 5 ROWS WITH TIES;

       VAL
----------
        10
        10
         9
         9
         8
         8

6 rows selected.

Top x% of rows

SELECT val
FROM   rownum_order_test
ORDER BY val
FETCH FIRST 20 PERCENT ROWS ONLY;

       VAL
----------
         1
         1
         2
         2

4 rows selected.

Using an offset, very useful for pagination

SELECT val
FROM   rownum_order_test
ORDER BY val
OFFSET 4 ROWS FETCH NEXT 4 ROWS ONLY;

       VAL
----------
         3
         3
         4
         4

4 rows selected.

You can combine offset with percentages

SELECT val
FROM   rownum_order_test
ORDER BY val
OFFSET 4 ROWS FETCH NEXT 20 PERCENT ROWS ONLY;

       VAL
----------
         3
         3
         4
         4

4 rows selected.


http://stackoverflow.com/questions/470542/how-do-i-limit-the-number-of-rows-returned-by-an-oracle-query-after-ordering

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