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Handling information overload: Showing data on demand in an IR

Using APEX Interactive Reports you can let the user decide which columns to show or hide in a report. But even then, reports with over 20 columns are still being used. So I tried to come up with a solution where you can hide less important (detail) column information and still reveal that information with minimal effort - like a mouse-over event. In this tiny example the list of employees of a department pops up when the user moves his mouse over the little question mark icon.
By adding some HTML and Javascript in the select statement (I know, that is not a "best practice"...but if you've got a better idea, please drop a comment) and some CSS you can use this technique - even for more complex "detail" reports!
The select statement used in this example is:
select dept.deptno
, dname
, loc
, 'onmouseover="javascript:$(''.overlay'').hide();$x_Toggle('''||dept.DEPTNO||''')">'||
'' enames
from dept
, ( select deptno, listagg( ename, ', ') within group (order by sal) enames
from emp
group by deptno
) emps
where emps.deptno (+) = dept.deptno
The CSS used in that statement is defined by:
One remark: You should disable sorting, filtering etc. on the "enames" column, because that makes no sense...

Edit: Thanks to Alex (see comments) the solution can be changed to something more elegant:
Just select the ENAMES column, and set these properties
- Link Text = <img src="#IMAGE_PREFIX#apps_info.gif" alt=""></a><div class="overlay" id="#DEPTNO#" style="display:none">#ENAMES#</div>
- Link Attributes = onmouseover="javascript:$('.overlay').hide();$x_Toggle('#DEPTNO#');"
- Target (URL) = javascript:void(0);

So the SQL is "clean" now and you even can enable the sorting etc again!

Comments

Jon Barwell said…
LISTAGG - Now have a reason to move to 11gR2
Anonymous said…
Somewhat unrelated to the original post, but I wanted to point out that Tom Kyte has a 'stragg' and 'clobagg' function available for download (from somewhere...probably asktom) that provides this functionality.

Paul Duncan
Roel said…
Paul, Jon,
Of course you can use any function you want. The listagg is just used as an example.
Thanks for commenting though.
Roel
suPPLer said…
Hi, Roel!

>> By adding some HTML and Javascript in the select statement (I know, that is not a "best practice"...but if you've got a better idea, please drop a comment)

How about this: Report Attributes->Column Attributes->Edit Column->Column Formatting->HTML Expression? You can make a hidden column ENAMES and use it values in HTML Expression for other column.

Alex.
Roel said…
Hi Alex,
That would be a good solution...if it was a 'regular' report. With an Interactive Report you don't have those options.
Roel
suPPLer said…
Roel,

Yes, but with an IR you still have a link section in the column attributes, don't you? It lets you specify text or HTML for a link, and you can use its Link Attributes field for assigning a class, that you can use as a jQuery selector in a Page HTML Header script. And you can put directly there all this JavaScript handler for the mouseover event (since it will be hard to read and to edit) or only a call to the function, that's defined in other place (e.g. Region Header).

PS: Sorry for my bad English, I have a little practice.
Roel said…
Hi Alex,
That is a good idea (why didn't I think of that?)!
Now I just selected my ENAMES column, set these properties
- Link Text = <img src="#IMAGE_PREFIX#apps_info.gif" alt=""></a><div class="overlay" id="#DEPTNO#" style="display:none">#ENAMES#</div>
- Link Attributes = onmouseover="javascript:$('.overlay').hide();$x_Toggle('#DEPTNO#');"
- Target (URL) = javascript:void(0);

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