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Why does typeof array with objects return “object” and not “array”? [duplicate]
Why is an array of objects considered an object, and not an array? For example:
4 Answers
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What are database normal forms and can you give examples? [closed]
...imply normalization, which is a process of organizing columns (attributes) and tables (relations) to reduce data redundancy and improve data integrity. (as written on Wikipedia ).
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Recursive Lock (Mutex) vs Non-Recursive Lock (Mutex)
... to be recursive. That means the same thread can lock the same mutex twice and won't deadlock. Of course it also needs to unlock it twice, otherwise no other thread can obtain the mutex. Not all systems supporting pthreads also support recursive mutexes, but if they want to be POSIX conform, they h...
Is “IF” expensive?
...can't, for the life of me, remember what exactly our teacher said that day and I'm hoping you would probably know.
16 Answe...
What is a stored procedure?
What is a "stored procedure" and how do they work?
17 Answers
17
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Why doesn't Java allow overriding of static methods?
...nce of a class. The point of polymorphism is that you can subclass a class and the objects implementing those subclasses will have different behaviors for the same methods defined in the superclass (and overridden in the subclasses). A static method is not associated with any instance of a class so ...
Shell script - remove first and last quote (") from a variable
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There's a simpler and more efficient way, using the native shell prefix/suffix removal feature:
temp="${opt%\"}"
temp="${temp#\"}"
echo "$temp"
${opt%\"} will remove the suffix " (escaped with a backslash to prevent shell interpretation).
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Good reasons to prohibit inheritance in Java?
... Item 19 of Joshua Bloch's excellent book "Effective Java", called "Design and document for inheritance or else prohibit it". (It's item 17 in the second edition and item 15 in the first edition.) You should really read it, but I'll summarize.
The interaction of inherited classes with their parent...
When and why JPA entities should implement Serializable interface?
The question is in the title. Below I just described some of my thoughts and findings.
14 Answers
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Get file size, image width and height before upload
How can I get the file size, image height and width before upload to my website, with jQuery or JavaScript?
7 Answers
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