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What is the “continue” keyword and how does it work in Java?
I saw this keyword for the first time and I was wondering if someone could explain to me what it does.
13 Answers
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When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
...t's not strictly necessary there. Where it IS necessary is for loops, and IF statements, etc, where you need more then one step...
IF EXISTS (SELECT * FROM my_table WHERE id = @id)
BEGIN
INSERT INTO Log SELECT @id, 'deleted'
DELETE my_table WHERE id = @id
END
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Checking if a folder exists (and creating folders) in Qt, C++
In Qt, how do I check if a given folder exists in the current directory?
If it doesn't exist, how do I then create an empty folder?
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Difference between window.location.href=window.location.href and window.location.reload()
What is the difference between JavaScript's
12 Answers
12
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JavaScript DOM remove element
I'm trying to test if a DOM element exists, and if it does exist delete it, and if it doesn't exist create it.
5 Answers
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select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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C# Java HashMap equivalent
Coming from a Java world into a C# one is there a HashMap equivalent? If not what would you recommend?
7 Answers
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Skip download if files exist in wget?
...oading of the file. It just doesn't do anything after downloading the file if the file has already been fully retrieved. Is there anyway to prevent making the HTTP request if the file already exists? stackoverflow.com/questions/33203898/…
– ma11hew28
Oct 18 '...
How can I check whether an array is null / empty?
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There's a key difference between a null array and an empty array. This is a test for null.
int arr[] = null;
if (arr == null) {
System.out.println("array is null");
}
"Empty" here has no official meaning. I'm choosing to define empty a...
Ruby, !! operator (a/k/a the double-bang) [duplicate]
...y, the only two things that evaluate to false are false (itself) and nil.
If you negate something, that forces a boolean context. Of course, it also negates it. If you double-negate it, it forces the boolean context, but returns the proper boolean value.
For example:
"hello" #-> this is a s...