If that is in fact a business rule, you'd be wise to create a unique constraint for those columns in the database as well so that you know for sure. That is, after all, what they're for. :-)
Clark On Dec 10, 2009, at 11:30 AM, Johnny Miller wrote: > Just checked it to make sure. And yes both columns are unique. > > Thanks for the heads up. > > Johnny > > On Dec 10, 2009, at 2:42 AM, David Avendasora wrote: > >> >> On Dec 9, 2009, at 6:35 PM, Chuck Hill wrote: >> >>> >>> On Dec 9, 2009, at 3:25 PM, Johnny Miller wrote: >>> >>>> The table has two columns an "IP_FROM" and an "IP_TO", each contains an IP >>>> number. >>>> >>>> According to the manual after you convert an IP address to an IP number it >>>> can only resolve to one row in the database i.e. >>>> >>>> IP_FROM <= X <= IP_TO >>>> >>>> So, I'd assume that the multi-column PK would work because the combo of >>>> IP_FROM and IP_TO has to be unique. I've never created column pk like >>>> that before - can I find the info in the Apple supplied docs? >>> >>> Nothing to it, just mark both as primary key columns in Entity Modeler. >>> Look at a many to many join table for an example. >> >> If, for some reason, the combination of those two fields is not unique it >> can really confuse EOF. See my message from earlier on December 9th about >> duplicate pointers in an NSArray of related objects. >> http://lists.apple.com/archives/webobjects-dev/2009/Dec/msg00286.html >> >> If there's any way you can simply add a new column to the table that has a >> unique value in it and mark that as the PK, that would be even better. I >> really dislike compound PKs. >> >> Dave >> >> >>>> >>>> re: raw SQL. Yeah, I planned on that. >>>> >>>> Thanks a lot, >>>> >>>> Johnny >>>> >>>> >>>> On Dec 9, 2009, at 1:12 PM, Chuck Hill wrote: >>>> >>>>> Are the rows unique? If so, you can make a multi-column PK. EOF needs >>>>> _something_ to uniquely identify them if you want to make EOs out of the >>>>> data. You might also want to consider just raw SQL (raw rows) and / or >>>>> making a cache of these and avoiding the EO overhead. >>>>> >>>>> Chuck >>>>> >>>>> On Dec 9, 2009, at 3:04 PM, Johnny Miller wrote: >>>>> >>>>>> Hi, >>>>>> >>>>>> I just purchased a database that does IP address to country resolution. >>>>>> I'm reverse engineering the database into a Wonder Framework and I >>>>>> realized that the single table in the database doesn't have a primary >>>>>> key. WOLips doesn't like this and throws an error stating the entity >>>>>> does not have a primary key. >>>>>> >>>>>> Should I just create a primary key field and leave it blank? Or is >>>>>> there a better alternative? This is going to be a read only database. >>>>>> >>>>>> Thanks in advance, >>>>>> >>>>>> Johnny Miller >>>>>> Kahalawai Media Corp >>>>>> http://www.kahalawai.com >>>>>> >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Do not post admin requests to the list. They will be ignored. >>>>>> Webobjects-dev mailing list ([email protected]) >>>>>> Help/Unsubscribe/Update your Subscription: >>>>>> http://lists.apple.com/mailman/options/webobjects-dev/chill%40global-village.net >>>>>> >>>>>> This email sent to [email protected] >>>>> >>>>> -- >>>>> Chuck Hill Senior Consultant / VP Development >>>>> >>>>> Practical WebObjects - for developers who want to increase their overall >>>>> knowledge of WebObjects or who are trying to solve specific problems. >>>>> http://www.global-village.net/products/practical_webobjects >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>> >>>> Johnny Miller >>>> Kahalawai Media Corp >>>> http://www.kahalawai.com >>>> >>>> >>>> >>> >>> -- >>> Chuck Hill Senior Consultant / VP Development >>> >>> Practical WebObjects - for developers who want to increase their overall >>> knowledge of WebObjects or who are trying to solve specific problems. >>> http://www.global-village.net/products/practical_webobjects >>> >>> >>> >>> >>> >>> >>> >>> _______________________________________________ >>> Do not post admin requests to the list. They will be ignored. >>> Webobjects-dev mailing list ([email protected]) >>> Help/Unsubscribe/Update your Subscription: >>> http://lists.apple.com/mailman/options/webobjects-dev/webobjects%40avendasora.com >>> >>> This email sent to [email protected] >>> >>> >> >> David Avendasora >> Senior Software Engineer >> K12, Inc. >> >> ***** >> WebObjects Documentation Wiki : >> http://wiki.objectstyle.org/confluence/display/WO/ >> ***** >> WebObjects API: >> http://developer.apple.com/legacy/mac/library/documentation/MacOSXServer/Reference/WO54_Reference/index.html >> ***** >> > > Johnny Miller > Kahalawai Media Corp > http://www.kahalawai.com > > > > _______________________________________________ > Do not post admin requests to the list. They will be ignored. > Webobjects-dev mailing list ([email protected]) > Help/Unsubscribe/Update your Subscription: > http://lists.apple.com/mailman/options/webobjects-dev/cpmueller%40mac.com > > This email sent to [email protected] _______________________________________________ Do not post admin requests to the list. They will be ignored. Webobjects-dev mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/webobjects-dev/archive%40mail-archive.com This email sent to [email protected]
