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How to access the correct `this` inside a callback?
...nding information that adds meaning to the code that is being executed. It includes much more information than just the thisBinding.
So the value of this isn't "context", it's just one part of an execution context. It's essentially a local variable that can be set by the call to any object and in st...
How to use index in select statement?
...the column that the index is applied to within your conditions, it will be included automatically. You do not have to use it, but it will speed up queries when it is used.
SELECT * FROM TABLE WHERE attribute = 'value'
Will use the appropriate index.
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How to save a plot as image on the disk?
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I have extended this answer to include a reference to dev.print. There are two closely-related questions which I think need different answers. The second sub-question is basically "How do I save an image that I have already plotted to my screen?". Apologi...
What are the disadvantages of using persistent connection in PDO
...nt connections as a solution to anything.
Further, most modern databases (including PostgreSQL) have their own preferred ways of performing connection pooling that don't have the immediate drawbacks that plain vanilla PHP-based persistent connections do.
To clarify a point, we use persistent con...
Can regular expressions be used to match nested patterns? [duplicate]
...by my upbringing in Natural Language Processing and the automata theory it included.
– Torsten Marek
Sep 25 '08 at 15:31
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OpenSSL and error in reading openssl.conf file
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This is useful because XAMPP includes OpenSSL inside of Apache folder.
– Jimmy Adaro
Feb 18 '17 at 23:17
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The name 'ConfigurationManager' does not exist in the current context
...why this has to be done when most other assemblies can simply be called by including the 'using' statement?
– Dhaust
Sep 2 '10 at 5:44
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Convert string to binary in python
...anumeric strings, but will become important if you're processing text that includes characters not in the ascii character set.
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Can hash tables really be O(1)?
...t's try adding some randomness to this.
First suppose our hash table also includes a seed r, and r is assigned to a random number at construction time. We assign it once and then it's fixed for that hash table instance. Now let's revisit our pseudocode.
function get(a: Table with m buckets and see...
Difference between “or” and || in Ruby? [duplicate]
...igher precedence than or.
So, in between the two you have other operators including ternary (? :) and assignment (=) so which one you choose can affect the outcome of statements.
Here's a ruby operator precedence table.
See this question for another example using and/&&.
Also, be aware o...