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Stream vs Views vs Iterators
...e viewed much like a database view. It is a series of transformation which one applies to a collection to produce a "virtual" collection. As you said, all transformations are re-applied each time you need to fetch elements from it.
Both Iterator and views have excellent memory characteristics. Stre...
How can I return pivot table output in MySQL?
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That's a really neat one. Do you know if this is standards compliant across other platforms (like Postgres)?
– itsols
Oct 9 '14 at 13:37
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Performance of FOR vs FOREACH in PHP
...he array, that's where you'll start seeing differences between them (since one will need to copy the entire array, and the reference can just modify inline)...
As for the iterators, foreach is equivalent to:
$it->rewind();
while ($it->valid()) {
$key = $it->key(); // If using the ...
Initializing a list to a known number of elements in Python [duplicate]
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The first thing that comes to mind for me is:
verts = [None]*1000
But do you really need to preinitialize it?
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What is a stored procedure?
.... Let's say for each table you have an Insert, Update, Delete and at least one select based on the primary key, that means each table will have 4 procedures. Now take a decent size database of 400 tables, and you have 1600 procedures! And that's assuming you don't have duplicates which you probably ...
How to get div height to auto-adjust to background size?
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@MarkAmery One of the coolest things about background-image is that it can use CSS blend-modes, whereas img cannot.
– Aaron Gray
Nov 22 '16 at 2:47
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Rails: Missing host to link to! Please provide :host parameter or set default_url_options[:host]
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I have done very similar to this and setting the default_url_option for action_mailer won't help. The use case is similar to this: Rails.application.routes.url_helpers.message_image_url(2)
– Boti
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Host 'xxx.xx.xxx.xxx' is not allowed to connect to this MySQL server
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One has to create a new MySQL User and assign privileges as below in Query prompt via phpMyAdmin or command prompt:
CREATE USER 'username'@'localhost' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON *.* TO 'username'@'loc...
What's the best way to distribute Java applications? [closed]
Java is one of my programming languages of choice. I always run into the problem though of distributing my application to end-users.
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How can I use an array of function pointers?
...* address of mul() */
p[3] = div; /* address of div() */
[...]
To call one of those function pointers:
result = (*p[op]) (i, j); // op being the index of one of the four functions
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