Oracle SQL: How limit the number of rows in a query

[ATC]

I have got a query that returns thousands of rows but I'm only interested in the first 20 records. In mysql I can limit the returned data (and thus the network traffic) with the LIMIT start,number clause, where start is the starting row and number is the number of rows that I want to see.

Is something similar possible in Oracle as well?

[ATC]

Oracle has a system attribute ROWNUM for each record returned. A query that only returns the first 20 records would look like the one in the example.

ROWNUM starts counting with 1.

// mysql
select col from tbl limit 20;

// Oracle
select col from tbl where rownum<=20;

// Microsoft SQL
select top 20 col from tbl;

Source: http://www.delphifaq.com/faq/databases/oracle/f594.shtml