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Deleting an object in java?
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You should remove the references to it by assigning null or leaving the block where it was declared. After that, it will be automatically deleted by the garbage collector (not immediately, but eventually).
Example 1:
Object a = new Object();
a = null; // after this, if t...
What is the difference between UNION and UNION ALL?
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UNION removes duplicate records (where all columns in the results are the same), UNION ALL does not.
There is a performance hit when using UNION instead of UNION ALL, since the database server must do additional work to remove the duplicate rows, but usually you do not want ...
How to get current time and date in C++?
Is there a cross-platform way to get the current date and time in C++?
24 Answers
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What is the best way to implement a “timer”? [duplicate]
...ent a timer? A code sample would be great! For this question, "best" is defined as most reliable (least number of misfires) and precise. If I specify an interval of 15 seconds, I want the target method invoked every 15 seconds, not every 10 - 20 seconds. On the other hand, I don't need nanosecond ac...
Designing function f(f(n)) == -n
A question I got on my last interview:
118 Answers
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How can you disable Git integration in Visual Studio 2013 permanently?
I know that you can disable git integration by using the Tools / Options dialog, but what I've noticed is that this setting doesn't seem to persist across sessions; i.e., as soon as close and reopen the solution, Git integration is enabled again. I'm guessing Visual Studio is seeing the .git folder ...
Using tags to turn off caching in all browsers? [duplicate]
...don't have access to the web server's headers you can turn off the cache using:
6 Answers
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How can I plot separate Pandas DataFrames as subplots?
I have a few Pandas DataFrames sharing the same value scale, but having different columns and indices. When invoking df.plot() , I get separate plot images. what I really want is to have them all in the same plot as subplots, but I'm unfortunately failing to come up with a solution to how and would...
Why use iterators instead of array indices?
Take the following two lines of code:
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Copy array by value
When copying an array in JavaScript to another array:
34 Answers
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