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Find MongoDB records where array field is not empty
... To me that's the correct approach, since it makes sure the array exists and is not empty.
– LeandroCR
Mar 19 '15 at 14:34
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‘ld: warning: directory not found for option’
...includes the -F flag, then delete the values in Framework Search Paths
And regarding the second error, sorry i can't help you out with that one. Hope someone else can help you out.
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impro...
How many levels of pointers can we have?
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The C standard specifies the lower limit:
5.2.4.1 Translation limits
276 The implementation shall be able to translate and execute at least one program that contains at least one instance of every one of the following limits...
How do I implement an Objective-C singleton that is compatible with ARC?
How do I convert (or create) a singleton class that compiles and behaves correctly when using automatic reference counting (ARC) in Xcode 4.2?
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What is the difference between getFields and getDeclaredFields in Java reflection
I'm a little confused about the difference between the getFields method and the getDeclaredFields method when using Java reflection.
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Type-juggling and (strict) greater/lesser-than comparisons in PHP
PHP is famous for its type-juggling. I must admit it puzzles me, and I'm having a hard time to find out basic logical/fundamental things in comparisons.
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Sort array of objects by string property value
...are function body: return a.value - b.value; (ASC)
– Andre Figueiredo
Jan 8 '14 at 12:06
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@Cerb...
When to use a “has_many :through” relation in Rails?
I am trying to understand what has_many :through is and when to use it (and how). However, I am not getting it. I am reading Beginning Rails 3 and I tried Googling, but I am not able to understand.
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“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
...Connector/J, configure the MySQL server with character_set_server=utf8mb4, and leave characterEncoding out of the Connector/J connection string. Connector/J will then autodetect the UTF-8 setting.
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Order of member constructor and destructor calls
Oh C++ gurus, I seek thy wisdom. Speak standardese to me and tell my if C++ guarantees that the following program:
4 Answer...