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offset oracle sql sql-limit sql-order-by

SQL (ORACLE): ORDER BY and LIMIT

I want do sorting by property ALL data in my db and ONLY AFTER that use LIMIT and OFFSET.

Query like this:

SELECT select_list
FROM table_expression
[ ORDER BY ... ]
[ LIMIT { number | ALL } ] [ OFFSET number ]

I know the sorting ends as soon as it has found the first row_count rows of the sorted result. Can I do sorting all data before calling LIMIT and OFFSET?

Prior to 12.1, Oracle does not support the LIMIT or OFFSET keywords. If you want to retrieve rows N through M of a result set, you’d need something like:

SELECT a.*
FROM (SELECT b.*,
rownum b_rownum
FROM (SELECT c.*
FROM some_table c
ORDER BY some_column) b
WHERE rownum <= <<upper limit>>) a
WHERE b_rownum >= <<lower limit>>

or using analytic functions:

SELECT a.*
FROM (SELECT b.*,
rank() over (order by some_column) rnk
FROM some_table)
WHERE rnk BETWEEN <<lower limit>> AND <<upper limit>>
ORDER BY some_column

Either of these approaches will sort give you rows N through M of the sorted result.

In 12.1 and later, you can use the OFFSET and/or FETCH [FIRST | NEXT] operators:

SELECT *
FROM some_table
ORDER BY some_column
OFFSET <<lower limit>> ROWS
FETCH NEXT <<page size>> ROWS ONLY