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Check if a row exists, otherwise insert
I need to write a T-SQL stored procedure that updates a row in a table. If the row doesn't exist, insert it. All this steps wrapped by a transaction.
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Can I use a hash sign (#) for commenting in PHP?
I have never, ever, seen a PHP file using hashes ( # ) for commenting. But today I realized that I actually can! I'm assuming there's a reason why everybody uses // instead though, so here I am.
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Enums and Constants. Which to use when?
I was doing some reading on enums and find them very similar to declaring constants. How would I know when to use a constant rather than an enum or vice versa. What are some of the advantages of using enums?
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Best way to pretty print a hash
I have a large hash with nested arrays and hashes. I would like to simply print it out so it 'readable' to the user.
12 An...
How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
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Checking images for similarity with OpenCV
Does OpenCV support the comparison of two images, returning some value (maybe a percentage) that indicates how similar these images are? E.g. 100% would be returned if the same image was passed twice, 0% would be returned if the images were totally different.
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Moment.js transform to date object
Using Moment.js I can't transform a correct moment object to a date object with timezones. I can't get the correct date.
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What does 'const static' mean in C and C++?
I saw this in some code here on StackOverflow and I couldn't figure out what it does. Then I saw some confused answers on other forums. My best guess is that it's used in C to hide the constant foo from other modules. Is this correct? If so, why would anyone use it in a C++ context where you can j...
Determine the number of lines within a text file
Is there an easy way to programmatically determine the number of lines within a text file?
11 Answers
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Postgres unique constraint vs index
As I can understand documentation the following definitions are equivalent:
8 Answers
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