What are Pharaoh, Grandmother, and Monarchy deletion patterns? - django

I was looking at the docs for Django CTE Trees and saw the text:
Multiple delete semantics: supports Pharaoh, Grandmother, and Monarchy deletion patterns.
This meant nothing to me, so I did a bit of googling - and found nothing!
Does anyone know what "Pharaoh, Grandmother, and Monarchy deletion patterns" are?

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SwiftUI - Drag Item From One List to Another

There are a few posts on SO asking the same thing as me, but I haven't really found a good answer to this question (some solutions only work for iPad, others say it is not possible in SwiftUI). Hoping that someone has more information since I can't find recent discussion on this topic.
In SwiftUI, it is easy to enable "edit" mode on a single list to reorder its items. I am wondering if there is a way to reorder items between two (or more) lists. Not looking for fully fledged out code, but maybe some direction and pointers since I am new to Swift.
Desired Behavior: https://imgur.com/4k69Rvi

How do you read the Railo documentation?

I was reading Ben Nadel's post about the isnull function and my initial thought was "wait: there's an isnull function in ColdFusion? I didn't know that! I wonder if there's one in Railo?" So I typed:
railo isnull
into google and this was the first link. In fact, a lot of my Railo searches have been to similar pages, so apparently this is something that I'm supposed to be able to read and understand. Here's my question:
Q: How do you read the Railo documentation?
I'm used to seeing words written out in sentence format like Ben's post. I mean: I can see that a lot of work went into this page, so I should try to squeeze some kind of meaning out of it... When I see for example:
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Does that mean anything to an applications programmer like myself, or is that a kind of internal documentation? I followed the link to the actual source code, but that's almost too much information.
Maybe I've identified a need.
You read the Railo Javadoc API the same way you read any Javadoc API.
(Though as you note this is more internal documentation and most CFML developers wont need to.)
If you want Railo's CFML documentation for isNull, you visit railodocs.org/isNull instead.
I don't know why Google isn't capable of finding the correct pages. :/
For the benefit of Google I'll also throw in these other links to the isNull documentation: http://railodocs.org/function/isnull?version=current and http://railodocs.org/index.cfm/function/isnull/version/current - they all display the same content (which may be a factor in why they're not ranked properly), so if someone reminds me later I'll bug Mark about getting the URLs canonicalised.
Railo does have isNull()
It works on variables that are not strings
It works on strings
In my experience, Railo 4.2 more or less supports CFML at the same level as ColdFusion 10. It is always useful to test. I agree that as of early 2014, Railo's documentation is lacking a certain clarity.

Zurb foundation 4 classes

Is there any documentation that explains each class in foundation.css? I am not great at front-end development and don't seem to be grasping the concepts with just cursory documentation available on zurb's site. Thanks in advance.
There is none. I think it will be tough for them, the ZURBlings, and overly-exhausting for us, to go over it, documented. I think what you need to know is what Responsive Design is all about. You can have a good beginner's introduction here:
From Wikipedia - a bird's eye
view
Another bird's eye view of
RD
Then continue on reading what Foundation is basically about.
And once you have a broader knowledge of what RD and Foundation is basically about, you can go crazy about it here and learn that it can actually allow you do more.
You really need to learn about their css once you are comfortable using Foundation, having read the links I gave you, and want to start to tweaking some of the configuration - which by the way is already explained in their docs.
AFAIK, there is no document that explains each and every class, but you can try to look at the kitchensink
http://foundation.zurb.com/docs/v/4.3.2/components/kitchen-sink.html
They have (almost) every component available as a demo in a single page. So you could inspect each of these elements and familiarize yourself with the class names.
This applies only to F4, I don't see a kitchen sink in F5

coldfusion 9 using cfsearch on verity returns -1705 error

I've created a collection in verity, but when I use cfsearch on it I get this error:
Message: There was a problem executing the cfSearch tag with the following collections.
Detail: Collection (status code): asktheexpert (-1705)
I have restarted the search service to no avail.
any tips?
From what I can gather from various googling, this indicates some sort of index corruption, and in general people never really worked out why. But if you purge & reindex your collection, it should go away.
I haven't used Verity in an age, but my experiences that most "weird errors" (one of which was this very one) were "solved" with a purge/reindex.
Ref: http://www.coldfusionjedi.com/index.cfm/2006/4/5/Verity-1-Me-1705 (and others along a similar vein, but Ray's probably the most reliable).
Are you in a position to migrate away from Verity? It's dead technology and will be dropped from CF in the next release. It might be a good idea to think about migrating to Solr if you haven't already got plans afoot to do so.
EDIT:
Another thing I've read today about this is that it might crop up when the collection is using one language, and the index and/or search are using different languages. Given you're transporting code between dev & prod, perhaps just verify that the collection language is the same as the index & search language.
Other than that - and my suggestions below about destroying various bits and pieces and starting again :-/ - I'm out of ideas.

How do you structure a database for a wiki site?

What's does the table look like- is there only one? How do you revert to older versions? Similar to how Stack overflow works.
The best way to go about this is to look at other software such as MediaWiki and see how they structure their database. Then you can pick and choose what you want to use to start off on your own wiki design.
On the other hand, you could always start off with a pretty basic spread of tables that would keep track of Users, Articles, Revisions on an Article, etc. and start spiraling out from there.
Mediawiki details in their help pages how they layout their database.
I agree with CookieOfFortune's comment that you should take a look at an existing open source wiki to see how they do it, but I'll also offer this thought prefixed with the fact that I have no experience writing wiki software. Maybe some sort of partial star schema could be useful in maintaining the previous versions.