Yes there are pitfalls! I have seen some questions in the bi publisher forum about converting all of a companies "existing report6i code" to BI Publisher. Don’t get me wrong the tool is a great, but like any tool it has some issues.
Here are some common elements as far as time is concerned for report development in general. These estimates are based my experience writing reports in the 11i e-business suite.
New Reports – From dev -->test -->production typically development time is about 40 hours.
Fixing an Existing report – If you’re lucky, 2 minutes but on average 5 about hours.
Converting/Copying an existing report 10-15 hours
Converting reports6i to BI Publisher
Small report 10 hours
Large report 20-40 hours, it can get ugly!
You may be asking yourself, what in the duce? How is that possible that converting a large report could take upto 40 hours? There are some bugs in the conversion tool. As example:
Function get_item_no return char
Where item_id = :item_id;
Conversion to PL/SQL:
Function get_item_no (item_id in number) return char
Where item_id = item_id;
Data Template Issues
In the converted PL/SQL example you can see the problem in grey. Sometimes during the conversion the parameters end up having the same name to a joining column. Ouch, get_item_no will actually compile too (note: it really shouldn’t in "theory" since item_id is “technically” ambiguous). Now were left with a situation where that function will blow up 100% no matter where it’s called from. Some reports can have over 50+ functions. When this issue occurs you have to fix each query and narrow it down in the data template.
Format Template Issues
Another kind of nasty issue is caused by sloppy development in reports6i with srw.set_field(….). This "was" a way of changing the data on a field in the report format trigger. It’s a big no, no. Well, guess what, set_field never gets converted to the format template so we have to fix the issue manually. Something like this is really easy to slip through the cracks. Also, did I mention that all the logic in your format triggers to suppress fields or groups, change colors, fonts, etc doesn’t get converted as well? Now that will take some dev time!
The one thing to come away from this article is this: Don’t fix things that aren’t broken (it’s easy to say, hard to practice). It’s a lot of work to convert a large report and troubleshooting the conversion issues will cost you time and money. Also, expect to feel a majority of the pain in the format template conversion. Formatting is the number one challenge for any report!
When the conversion tool becomes a more mature product we can expect the conversion to be better and it “might” make sense to convert more of your organizations reports. The only justification for this would be either lower cost of support or a disappearing reports6i skill set in your organization/development community. With that in mind, if you don’t have a choice and you have to convert a report, the tool does a pretty good job and it’s better than nothing.