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What is the difference between Non-Repeatable Read and Phantom Read?
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and
A phantom read occurs when, in the course of a transaction, two identical queries are executed, and the collection of rows returned by the second query is different from the first.
Simple examples:
User A runs the same query twice.
In between, User B runs a transaction and commits.
N...
JSON: why are forward slashes escaped?
... when embedding JSON in a <script> tag, which doesn't allow </ inside strings, like Seb points out.
Some of Microsoft's ASP.NET Ajax/JSON API's use this loophole to add extra information, e.g., a datetime will be sent as "\/Date(milliseconds)\/". (Yuck)
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How to undo another user’s checkout in TFS?
As the resident TFS admin, on occasion I am asked to undo a checkout (usually a lock) that a user has on a certain file checked into source control.
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How to pass a class type as a function parameter
... I'm making a button. In that button's code (it's SpriteKit, so inside touchesBegan) I want the button to call a Class function, so need a reference to that class. So in the Button Class I have created a variable to hold a reference to the Class. But I can't get it to hold a Class, or the Ty...
Use a URL to link to a Google map with a marker on it
...llowing document:
https://developers.google.com/maps/documentation/urls/guide
You can use URLs in search, directions, map and street view modes.
For example, to show the marker at specified position you can use the following URL:
https://www.google.com/maps/search/?api=1&query=36.26577,-92.5...
Loop through files in a directory using PowerShell
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If you need to loop inside a directory recursively for a particular kind of file, use the below command, which filters all the files of doc file type
$fileNames = Get-ChildItem -Path $scriptPath -Recurse -Include *.doc
If you need to do the filt...
List vs Set vs Bag in NHibernate
...o v4) or System.Collections.Generic.ISet (NH v4+). It is important to override GetHashCode and Equals to indicate the business definition of duplicate. Can be sorted by defining an orderby or by defining a comparer resulting in a SortedSet result.
Bag: Unordered list of entities, duplicates allowed....
Parsing IPv6 extension headers containing unknown extensions
...but then that's their fate anyway.
Edited to add: This design means that middleboxes can only change what they know. If a middlebox sees a header it doesn't know, then it has only two options: Reject or pass on. In IPv4 it could also remove the unknown extension and pass on the rest. IMO this prope...
Git submodule add: “a git directory is found locally” issue
...m other suggestions was your step #3. Thanks!
– AndroidDev
May 14 '16 at 17:36
8
Steps 2 & 3 ...
Order discrete x scale by frequency/value
...cyl2)) + geom_bar()
As James pointed out in his answer, reorder is the idiomatic way of reordering factor levels.
mtcars$cyl3 <- with(mtcars, reorder(cyl, cyl, function(x) -length(x)))
ggplot(mtcars, aes(cyl3)) + geom_bar()
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