RE: Revisited: Oracle and the empty string
You might handle this by defining fields which allow null to be optional in your XML. E.g., tag not in XML = NULL / tag exists and is empty = . I think the XML parsers can differentiate between these with some extra code. FYI - You might want to take a look at: http://torque-addons.sourceforge.net/XML-Import-Export/index.html This is some code I wrote a while back to support import/export of data into one of my systems. I've also used it as a basis for some REST services I added. -Original Message- From: Thomas Fischer [mailto:fisc...@seitenbau.net] Sent: Friday, October 01, 2010 4:29 PM To: Apache Torque Users List Subject: Re: Revisited: Oracle and the empty string Thomas Vandahl t...@apache.org wrote: On 01.10.10 21:47, Thomas Fischer wrote: In my experience, it is no problem if you keep that fact in mind. It just makes the code non-portable to another database (you only query for not null and know it's also not empty in oracle, but not dor other databases). Is it a problem for yaou if and null get mapped to the same value ? Unfortunately it is. The XML processing is different for these cases. Suggestions are welcome. Patch it in the template to some strange value? Other ideas? I do not understand the problem well enough (perhaps you can provide a little code example ?) but what you could do is to use the first characte of the String in the database as a flag: N for null and O for other (not null). You can overwrite the setters and getters such that they add and remove the flag automatically. You could use the template override mechanism in Torque4 to do this with minimum impact. There is a similar example in the torque4 test project (use the overrideConfigDir to override certain template settings). If you look at it and there is not enough documentation just open a jira issue. Thomas - To unsubscribe, e-mail: torque-user-unsubscr...@db.apache.org For additional commands, e-mail: torque-user-h...@db.apache.org DukeCE Privacy Statement: Please be advised that this e-mail and any files transmitted with it are confidential communication or may otherwise be privileged or confidential and are intended solely for the individual or entity to whom they are addressed. If you are not the intended recipient you may not rely on the contents of this email or any attachments, and we ask that you please not read, copy or retransmit this communication, but reply to the sender and destroy the email, its contents, and all copies thereof immediately. Any unauthorized dissemination, distribution or copying of this communication is strictly prohibited. - To unsubscribe, e-mail: torque-user-unsubscr...@db.apache.org For additional commands, e-mail: torque-user-h...@db.apache.org
RE: Revisited: Oracle and the empty string
just a question about a best-practice. We are trying to implement an XML-to-DB-mapper service on Oracle. The (existing) XSD defines some fields which distinguish between not set (null) and empty (). How do others handle this in Oracle? Especially within Torque? In my experience, it is no problem if you keep that fact in mind. It just makes the code non-portable to another database (you only query for not null and know it's also not empty in oracle, but not dor other databases). Is it a problem for yaou if and null get mapped to the same value ? an aside: Others (empire-db in the incubator) have tried to make this portable by always mapping to null for all databases, but I do not think this is a good idea either. No ideal solution of this problem is known to me. Thomas - To unsubscribe, e-mail: torque-user-unsubscr...@db.apache.org For additional commands, e-mail: torque-user-h...@db.apache.org
Re: Revisited: Oracle and the empty string
On 01.10.10 21:47, Thomas Fischer wrote: In my experience, it is no problem if you keep that fact in mind. It just makes the code non-portable to another database (you only query for not null and know it's also not empty in oracle, but not dor other databases). Is it a problem for yaou if and null get mapped to the same value ? Unfortunately it is. The XML processing is different for these cases. Suggestions are welcome. Patch it in the template to some strange value? Other ideas? Bye, Thomas - To unsubscribe, e-mail: torque-user-unsubscr...@db.apache.org For additional commands, e-mail: torque-user-h...@db.apache.org
Re: Revisited: Oracle and the empty string
Thomas Vandahl t...@apache.org wrote: On 01.10.10 21:47, Thomas Fischer wrote: In my experience, it is no problem if you keep that fact in mind. It just makes the code non-portable to another database (you only query for not null and know it's also not empty in oracle, but not dor other databases). Is it a problem for yaou if and null get mapped to the same value ? Unfortunately it is. The XML processing is different for these cases. Suggestions are welcome. Patch it in the template to some strange value? Other ideas? I do not understand the problem well enough (perhaps you can provide a little code example ?) but what you could do is to use the first characte of the String in the database as a flag: N for null and O for other (not null). You can overwrite the setters and getters such that they add and remove the flag automatically. You could use the template override mechanism in Torque4 to do this with minimum impact. There is a similar example in the torque4 test project (use the overrideConfigDir to override certain template settings). If you look at it and there is not enough documentation just open a jira issue. Thomas - To unsubscribe, e-mail: torque-user-unsubscr...@db.apache.org For additional commands, e-mail: torque-user-h...@db.apache.org
