Hi, Scott, The last email John sent outlines the key steps for creating and handling new/custom columns. This is my effort to give you an example how I dealt with creating custom column.
(attached 3 files) My goal is to have transparent serialization/de-serialization of perl structures into blob columns. First, I defined in my custom Metadata class (Metadata.pm, lines 18-20) that blob types of columns will be handled by my custom column class -- Metadata::Column::Storable. I created the column class by stripping down Metadata::Column::Bitfield (as John suggested) class from RDBO package. Then I specified which will be the method maker for this column (Metadata_Column_Storable.pm, line 23) - MakeMethods::Storable. Again, I took `bitfield' sub from Rose::DB::Object::MakeMethods::Generic and actually wrote the code for serializing/de-serializing. For your case, you should write your time handling functions in the latter module and just global replace 'storable' with 'mypgtime' in former 2 modules. Hope that helps! On separate subject: John, thank you for bringing the attention to RDBO::Util's functions is_loading/is_saving -- I used to use undocumented STATE_LOADING() as seen in bitfield. Regards, Svi 2006/1/11, Svilen Ivanov <[EMAIL PROTECTED]>: > Hi Scott, > > I've done something similar you want to. I use blob column to store > arbitrary perl structure in serialized way (via Storable) and retrieve > it back and un-serialize it transparently. I'll send you my sample > code for reference in few hours (when I get home). > > Generally, your goal can be achieve by adding load/save triggers on > standard column types. Check this: > http://search.cpan.org/~jsiracusa/Rose-DB-Object-0.62/lib/Rose/DB/Object/Metadata/Column.pm#TRIGGERS > > Also, you can follow this thread discussing inflating/deflating values > in DB with triggers: > http://sourceforge.net/mailarchive/forum.php?thread_id=9267247&forum_id=46239 > > > 2006/1/11, Scott Karns <[EMAIL PROTECTED]>: > > Hello again. > > > > I've made significant progress in my understanding of > > RDBO since I last requested help here, thanks again, > > John. > > > > My current problem is that the database I'm working > > with contains two column types that are specific to > > postgres and don't seem to be supported by RDBO. The > > first I alluded to in an earlier message, the 'OID' > > column type that I am using to store what amounts to > > blob data (an image file actually) and the second is a > > 'time' column type used to store class (as in school) > > scheduling information. For now, I can make do without > > the 'OID' column type, but it's critical that I be > > able to use the 'time' type. > > > > After looking through some of the RDBO::Metadata > > space, I believe my best bet is to create a new scalar > > column class that will convert the Pg data to an > > integer upon access and back to the Pg form upon store > > as well as some ability to play well with timestamp > > objects. > > > > My problem is that I'm struggling a bit with the OO > > aspect of the code and could use some guidance about > > how best to approach this. I feel like I'm asking for > > someone else to write the code, but I'm really only > > looking for some help getting started. > > > > Scott > > > > __________________________________________________ > > Do You Yahoo!? > > Tired of spam? Yahoo! Mail has the best spam protection around > > http://mail.yahoo.com > > > > > > ------------------------------------------------------- > > This SF.net email is sponsored by: Splunk Inc. Do you grep through log files > > for problems? Stop! Download the new AJAX search engine that makes > > searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! > > http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click > > _______________________________________________ > > Rose-db-object mailing list > > Rose-db-object@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/rose-db-object > > >
MakeMethods_Storable.pm
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Metadata.pm
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Metadata_Column_Storable.pm
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