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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...rst time you iterate over it. For example, this will print the headline of all entries in the database:
for e in Entry.objects.all():
print e.headline
So your ten million rows are retrieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait ...
Easy pretty printing of floats in python?
...
It's an old question but I'd add something potentially useful:
I know you wrote your example in raw Python lists, but if you decide to use numpy arrays instead (which would be perfectly legit in your example, because you seem to be dealing with arrays of numbers), there is ...
How do I convert from int to String?
I'm working on a project where all conversions from int to String are done like this:
20 Answers
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Do I have to guard against SQL injection if I used a dropdown?
... make sure the posted size is what you expect.
$possibleOptions = array('All', 'Large', 'Medium', 'Small');
if(in_array($_POST['size'], $possibleOptions)) {
// Expected
} else {
// Not Expected
}
Then use mysqli_* if you are using a version of php >= 5.3.0 which you should be, to sav...
Simple example of threading in C++
...ill execute, followed by the function's parameters. The thread is automatically started upon construction.
If later on you want to wait for the thread to be done executing the function, call:
t1.join();
(Joining means that the thread who invoked the new thread will wait for the new thread to fi...
Cookies on localhost with explicit domain
...unction.setcookie.php#73107.
If working with the Java Servlet API, don't call the cookie.setDomain("...") method at all.
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Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?
...ved would be the fastest way, though I kept thinking that adding a method call may make it slower...
function StringBuilder() {
this._array = [];
this._index = 0;
}
StringBuilder.prototype.append = function (str) {
this._array[this._index] = str;
this._index++;
}
StringBuilder.pro...
Where to place AutoMapper.CreateMaps?
...t of overhead. I'm not too sure how to design my application to put these calls in just 1 place.
10 Answers
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How do I use the includes method in lodash to check if an object is in the collection?
...
The includes (formerly called contains and include) method compares objects by reference (or more precisely, with ===). Because the two object literals of {"b": 2} in your example represent different instances, they are not equal. Notice:
({"b": 2}...
How do I set a variable to the output of a command in Bash?
... be done with $(command) or "$(command)", which I find easier to read, and allows for nesting.
OUTPUT=$(ls -1)
echo "${OUTPUT}"
MULTILINE=$(ls \
-1)
echo "${MULTILINE}"
Quoting (") does matter to preserve multi-line variable values; it is optional on the right-hand side of an assignment, as w...