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Why create “Implicitly Unwrapped Optionals”, since that implies you know there's a value?
...iewDidLoad() you can assume that properties generally exist. Otherwise, in order to satisfy the compiler, you had to be using the
forced unwrapping,
optional binding
or optional chaining
only to obscure the main purpose of the code.
Above part from the Swift book refers also to the Automatic Re...
Any reason to write the “private” keyword in C#?
...e in C# (meaning that if I don't write public , protected , internal , etc. it will be private by default). (Please correct me if I am wrong.)
...
Error Code: 1005. Can't create table '…' (errno: 150)
...ey name to test for this.
One or both of your tables is a MyISAM table. In order to use foreign keys, the tables must both be InnoDB. (Actually, if both tables are MyISAM then you won’t get an error message - it just won’t create the key.) In Query Browser, you can specify the table type.
You ha...
Can a variable number of arguments be passed to a function?
...
# 1
# 2
# 3
# banan = 123
They must be both declared and called in that order, that is the function signature needs to be *args, **kwargs, and called in that order.
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What is a “Bitmap heap scan” in a query plan?
... is different from an index scan, where the index is visited row by row in order -- meaning a disk page may get visited multiple times.
Re: the question in your comment... Yep, that's exactly it.
An index scan will go through rows one by one, opening disk pages again and again, as many times as ...
Node.js Best Practice Exception Handling
...hrow, and the stack. But you have to know how to use promises correctly in order to take advantage of them."
Number2: Use only the built-in Error object
TL;DR: It pretty common to see code that throws errors as string or as a custom type – this complicates the error handling logic and the int...
How can mixed data types (int, float, char, etc) be stored in an array?
... it has many names (kind of like dictionaries, hashes, associative arrays, etc.).
– Barmar
Sep 2 '13 at 17:40
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What are the differences between git remote prune, git prune, git fetch --prune, etc
...oesn't affect your view of any branches.
git remote prune origin and git fetch --prune both operate on references under refs/remotes/... (I'll refer to these as remote references). It doesn't affect local branches. The git remote version is useful if you only want to remove remote references unde...
Are 2^n and n*2^n in the same time complexity?
...
You will have to go to the formal definition of the big O (O) in order to answer this question.
The definition is that f(x) belongs to O(g(x)) if and only if the limit limsupx → ∞ (f(x)/g(x)) exists i.e. is not infinity. In short this means that there exists a constant M, such that v...
How can I list all foreign keys referencing a given table in SQL Server?
...n I get a list of all the foreign key constraints I will need to remove in order to drop the table?
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