[sql] How to Select Top 100 rows in Oracle?

My requirement is to get each client's latest order, and then get top 100 records.

I wrote one query as below to get latest orders for each client. Internal query works fine. But I don't know how to get first 100 based on the results.

    SELECT * FROM (
      SELECT id, client_id, ROW_NUMBER() OVER(PARTITION BY client_id ORDER BY create_time DESC) rn 
      FROM order
    ) WHERE rn=1

Any ideas? Thanks.

First 10 customers inserted into db (table customers):

select * from customers where customer_id <=
(select  min(customer_id)+10 from customers)

Last 10 customers inserted into db (table customers):

select * from customers where customer_id >=
(select  max(customer_id)-10 from customers)

Hope this helps....

To select top n rows updated recently

SELECT * 
FROM (
   SELECT * 
   FROM table 
   ORDER BY UpdateDateTime DESC
)
WHERE ROWNUM < 101;

you should use rownum in oracle to do what you seek

where rownum <= 100

see also those answers to help you

limit in oracle

select top in oracle

select top in oracle 2

As Moneer Kamal said, you can do that simply:

SELECT id, client_id FROM order 
WHERE rownum <= 100
ORDER BY create_time DESC;

Notice that the ordering is done after getting the 100 row. This might be useful for who does not want ordering.

Try this:

   SELECT *
FROM (SELECT * FROM (
    SELECT 
      id, 
      client_id, 
      create_time,
      ROW_NUMBER() OVER(PARTITION BY client_id ORDER BY create_time DESC) rn 
    FROM order
  ) 
  WHERE rn=1
  ORDER BY create_time desc) alias_name
WHERE rownum <= 100
ORDER BY rownum;

Or TOP:

SELECT TOP 2 * FROM Customers; //But not supported in Oracle

NOTE: I suppose that your internal query is fine. Please share your output of this.