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using rownum with union  RSS feed

 
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In order implement pagination on the front end, I need specific number(1-10, 11-20 ..) of rows to be returned from the db.

I know we can use constraints like
select * from table Where ROWNUM < 10

However I'm using multiple (4) joins in my sql query to fetch data from oracle 10g db.

How do i achieve this.
 
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setMaxRows(int maxRows) on statement object
 
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If you want to fetch for each page then you need to use ORDER BY and ROWNUM. Let's say I join 3 tables emp, dept, loc and I need n rows at a time.

The query would be


You need to bind the values for ROWNUM predicate.

- ROWNUM does not ensure that records are fetched in any particular record. If you fire a query like
SELECT * FROM emp WHERE rownum < 10
Oracle does not guarantee you will get same set of 10 row very time. The ORDER BY clause will help to overcome this unpredictable behavior.
 
It is sorta covered in the JavaRanch Style Guide.
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