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MySQL: selecting rows where a column is null
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NULL = NULL is not really FALSE - it's NULL again. But it's not TRUE either, so IF(NULL = NULL) won't execute.
– Konerak
Jan 12 '11 at 19:50
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iOS JavaScript bridge
...t's something simple enough that you might give it a try yourself. I personally did exactly this when I needed to do that. You might also create a simple library that suits your needs.
1. Execute JS methods from Objective-C
This is really just one line of code.
NSString *returnvalue = [webView st...
What is the relationship between UIView's setNeedsLayout, layoutIfNeeded and layoutSubviews?
...fNeeded and layoutSubviews methods? And an example implementation where all three would be used. Thanks.
2 Answers
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Is the != check thread safe?
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Although strong evidence, bytecode is not actually a proof. It must be somewhere in the JLS as well...
– Marko Topolnik
Aug 27 '13 at 9:29
10
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Java equivalent to #region in C#
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Actually this can be achieved. If you scroll down on this post "Yaqub Ahmad" explains how to get this functionality. Also here is a link (kosiara87.blogspot.com/2011/12/…) that shows you how to add it to your existing eclipse e...
Convert a float64 to an int in Go
...problem in Go that can be unexpected (at least if you come from Java): "In all non-constant conversions involving floating-point or complex values, if the result type cannot represent the value the conversion succeeds but the result value is implementation-dependent." (golang.org/ref/spec#Conversion...
How to intercept click on link in UITextView?
...View shouldInteractWithURL:(NSURL *)URL inRange:(NSRange)characterRange *NS_DEPRECATED_IOS(7_0, 10_0, "Use textView:shouldInteractWithURL:inRange:forInteractionType: instead");*
to intercept the clicks to links. And this is the best way to do it.
For ios6 and earlier a nice way to do this is to b...
How to programmatically determine the current checked out Git branch [duplicate]
...ions/git-completion.bash does that for bash prompt in __git_ps1. Removing all extras like selecting how to describe detached HEAD situation, i.e. when we are on unnamed branch, it is:
branch_name="$(git symbolic-ref HEAD 2>/dev/null)" ||
branch_name="(unnamed branch)" # detached HEAD
branc...
Filter rows which contain a certain string
...n easily extend to more than one column.
Below also a solution with filter_all in order to find the string in any column,
using diamonds as example, looking for the string "V"
library(tidyverse)
String in only one column
# for only one column... extendable to more than one creating a column list in...
How to elegantly deal with timezones
...t is that inside the DB, date/times are stored in UTC. When on the server, all date/times should be dealt with in UTC. However, I see three problems that I'm trying to overcome:
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