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How to print last two columns using awk
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Note: this works only if at least two columns exist. On records with one column you will get a spurious "-1 column1"
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How can I copy data from one column to another in the same table?
...ork if you want to transfer old value to other column and update the first one: UPDATE table SET columnA = 'new value', columnB = columnA. Like other answer says - don't forget the WHERE clause to update only what's needed.
– Carl di Ortus
Feb 9 '18 at 8:45
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Entity Framework - Code First - Can't Store List
... In .NET Core you can. I'm using this exact piece of code in one of my projects.
– Sasan
Apr 8 '19 at 14:26
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How to get all properties values of a JavaScript Object (without knowing the keys)?
... If you are reading this answer, you should definitely read the other one
– mgarciaisaia
Dec 11 '15 at 23:35
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If i synchronized two methods on the same class, can they run simultaneously?
...n't simultaneously execute them on the same object from different threads (one of the two methods will block until the other is finished).
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When should you branch?
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There are several uses for branching. One of the most common uses is for separating projects that once had a common code base. This is very useful to experiment with your code, without affecting the main trunk.
In general, you would see two branch types:
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Best practices/performance: mixing StringBuilder.append with String.concat
...] array that grows when needed. No extra char[] is created if the internal one is sufficiently big.
stringBuilder.append(s1.concat(s2))
is also performing poorly because s1.concat(s2) creates an extra char[] array and copies s1 and s2 to it just to copy that new array contents to internal StringB...
Should I use pt or px?
What is the difference between pt and px in CSS? Which one should I use and why?
5 Answers
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Java optional parameters
...or explain the serious disadvantage caused by the possibility of more than one return value.
– Andreas Vogl
Dec 26 '19 at 11:05
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On design patterns: When should I use the singleton?
...that there are actually very few "acceptable" reasons to use a Singleton.
One reason that tends to come up over and over again on the internets is that of a "logging" class (which you mentioned). In this case, a Singleton can be used instead of a single instance of a class because a logging class u...