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What does it mean by select 1 from table?
... is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, common enough to be noted, even if it isn't really meaningful (that said, I will use it because others use it and it is "more obvious" im...
How to check iOS version?
...lable(iOS 9, *) {}
In Objective-C, you need to check the system version and perform a comparison.
[[NSProcessInfo processInfo] operatingSystemVersion] in iOS 8 and above.
As of Xcode 9:
if (@available(iOS 9, *)) {}
The full answer …
In Objective-C, and Swift in rare cases, it's better to...
Where to use EJB 3.1 and CDI?
I am making a Java EE based product in which I'm using GlassFish 3 and EJB 3.1.
2 Answers
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What is “thread local storage” in Python, and why do I need it?
...on-local variables (because each function call gets its own set of locals, and threads are always separate function calls.) And even then, only the variables themselves (the names that refer to objects) are local to the function; objects themselves are always global, and anything can refer to them.
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How to convert a String to its equivalent LINQ Expression Tree?
...o you mean by "writing a parser (using Expression under the hood)" Parsing and then generating an expression tree, or does System.Linq.Expressions have some parsing mechanism?
– AK_
Jul 1 '13 at 14:51
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Typescript: difference between String and string
Does anyone know the difference between String and string in TypeScript? Am I correct in assuming that they ought to be the same?
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How to run a Runnable thread in Android at defined intervals?
... developed an application to display some text at defined intervals in the Android emulator screen. I am using the Handler class. Here is a snippet from my code:
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Difference between an application server and a servlet container?
I am trying to understand the difference between a full fledged application server (e.g. Weblogic, JBoss etc.) and a servlet container (Tomcat, Jetty etc.).
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Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
...e with an ATmega328 . I am working on Ubuntu 12.04 (Precise Pangolin), and the Arduino IDE's version is 1.0. Recently, I tried to upload a few of the sample sketches onto it, such as the Blink one. However, none of my attempts are working and they result in the same error every time I try it:
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Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...utomated weather data from the web. The observations occur every 5 minutes and are compiled into monthly files for each weather station. Once I'm done parsing a file, the DataFrame looks something like this:
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