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How does MongoDB sort records when no sort order is specified?
...ll have the same data outcome when oplog updates are applied.
What if an index is used?
If an index is used, documents will be returned in the order they are found (which does necessarily match insertion order or I/O order). If more than one index is used then the order depends internally on whic...
Map over object preserving keys
...you could do something like this:
Object.keys(object).map(function(value, index) {
object[value] *= 3;
})
but that is confusing, when seeing map one would expect to have an array as result and then make something with it.
...
Dropping Unique constraint from MySQL table
...
A unique constraint is also an index.
First use SHOW INDEX FROM tbl_name to find out the name of the index. The name of the index is stored in the column called key_name in the results of that query.
Then you can use DROP INDEX:
DROP INDEX index_name O...
How can I represent an 'Enum' in Python?
...))). Then my_enum can be used in look-up, e.g., my_enum['Item0'] can be an index into a sequence. You might want to wrap the result of str.split in a function that throws an exception if there are any duplicates.
– Ana Nimbus
Jun 2 '18 at 3:51
...
Does pandas iterrows have performance issues?
...r some python structures), but a DataFrame does a fair number of checks on indexing, so this will always be very slow to update a row at a time. Much better to create new structures and concat.
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Google Espresso or Robotium [closed]
...ficant number of users (see: http://developer.android.com/about/dashboards/index.html). It works on some of the older versions, but testing on those would be a waste of resources. Speaking about testing... Espresso is tested on every change by a comprehensive test suite (with over 95% coverage) as w...
Where does Console.WriteLine go in ASP.NET?
... : System.IO.TextWriter {
public override void Write(char[] buffer, int index, int count) {
System.Diagnostics.Debug.Write(new String(buffer, index, count));
}
public override void Write(string value) {
System.Diagnostics.Debug.Write(value);
}
public override Encoding ...
How to loop through array in jQuery?
...upported in any version of IE.
jQuery.each:
jQuery.each(substr, function(index, item) {
// do something with `item` (or `this` is also `item` if you like)
});
(Link to docs)
Advantages: All of the same advantages as forEach, plus you know it's there since you're using jQuery.
Disadvantages...
Git 'fatal: Unable to write new index file'
...tried the following:
changing .git permssions (same issue)
changing .git/index permissions (same issue)
git add-ing all the changes to commit (same issue)
git rm-ing deleted files, since they were reporting file name too long errors (same issue)
git reset (soft|Head|Hard) (same issue)
git clean (s...
Is there a __CLASS__ macro in C++?
...
I would like to suggest boost::typeindex, which I learned about from Scott Meyer's "Effective Modern C++" Here's a basic example:
Example
#include <boost/type_index.hpp>
class foo_bar
{
int whatever;
};
namespace bti = boost::typeindex;
templat...