Pagination with pl/sql region.

Question

Hi all,
I have created one more sample page with pl/sql region
workspace: srijaks
login:[email protected]
password:srijakutty
Application: 49471 - Sample Field Display
page 16
Initially it will display the first two records of the concerned department.
but then by clicking the next and previous buttons it has to display the next two records and the previous 2 records respectively.
Please, if some one can help me !!!?
Thanks in advance
bye
Srikavi

Answer 1

Hi Srikavi,
OK - I've updated your page to get the next/previous buttons working. I have removed the bit in the PL/SQL code that assigned a value to the next button as this was causing me problems. I have also updated the select statement in this to include: and empno >= v('P16_EMPNO').
The next/previous buttons are based on:
Previous:
WITH EMPS AS (SELECT EMPNO, DENSE_RANK () OVER (ORDER BY EMPNO DESC) EMPNUMBER FROM EMP WHERE DEPTNO = :P16_SELECT_DEPT AND EMPNO < :P16_EMPNO ORDER BY EMPNO DESC)
SELECT NVL(MAX(EMPNO),0)
FROM EMPS
WHERE EMPNUMBER = 2Next:
WITH EMPS AS (SELECT EMPNO, DENSE_RANK () OVER (ORDER BY EMPNO) EMPNUMBER FROM EMP WHERE DEPTNO = :P16_SELECT_DEPT AND EMPNO > :P16_EMPNO ORDER BY EMPNO)
SELECT NVL(MIN(EMPNO),0)
FROM EMPS
WHERE EMPNUMBER = 2These are calculated Before Header and are unconditional
I have also added an Employees item that is set as:
{code
SELECT COUNT(*)
FROM EMP
WHERE DEPTNO = :P16_SELECT_DEPT
This is only calculated when the item is null - which will be the case when a new dept is selected - so this only happens once per selection.  This returns a correct record count - updating the select statement in the report as above, caused problems with the existing count.  Not sure if you want to change these back?
As you can see, I've assigned a ranking to each item - this could have been achieved using a row number as well.  There are several ways this could have been handled.  The next/previous buttons could be based on the ranking/rownumber value and the EMPNO retrieved based on this.  The EMPNOs could be queried into a collection and you could use the sequence numbers to move through the records.  The above is just one example - you might like to try the others to see which one you prefer.
Andy