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When to use single quotes, double quotes, and backticks in MySQL
I am trying to learn the best way to write queries. I also understand the importance of being consistent. Until now, I have randomly used single quotes, double quotes, and backticks without any real thought.
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What are enums and why are they useful?
Today I was browsing through some questions on this site and I found a mention of an enum being used in singleton pattern about purported thread safety benefits to such solution.
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Always pass weak reference of self into block in ARC?
...am a little confused about block usage in Objective-C. I currently use ARC and I have quite a lot of blocks in my app, currently always referring to self instead of its weak reference. May that be the cause of these blocks retaining self and keeping it from being dealloced ? The question is, sho...
Why is “throws Exception” necessary when calling a function?
Why compiler reports that methods show2() , show3() , and main() have
8 Answers
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How to use php serialize() and unserialize()
... means to put the structure into a "lower common denominator" that can be handled by things other than PHP, like databases, text files, sockets. The standard PHP function serialize is just a format to express such a thing, it serializes a data structure into a string representation that's unique to ...
What's the difference between a proc and a lambda in Ruby?
And when would you use one rather than the other?
8 Answers
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What's the difference between a Python “property” and “attribute”?
I am generally confused about the difference between a "property" and an "attribute", and can't find a great resource to concisely detail the differences.
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Is SQL syntax case sensitive?
Is SQL case sensitive. I've used MySQL and SQL Server which both seem to be case in-sensitive. Is this always the case? Does the standard define case-sensitivity?
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What is the difference between id and class in CSS, and when should I use them? [duplicate]
Here I gave an id to the div element and it's applying the relevant CSS for it.
15 Answers
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Eclipse will not start and I haven't changed anything
...aven't updated anything for at least a month. I was just working normally and suddenly the menus were all blank, so I decided to restart eclipse. I clicked "close" and "ok" to save everything, but nothing happened, so I clicked close again and eclipse closed. I clicked on eclipse and the loading sc...