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mongodb group values by multiple fields
...urse the ability to interpolate the variable through $expr using $match to select the matching items in the "join", but the general premise is a "pipeline within a pipeline" where the inner content can be filtered by matches from the parent. Since they are both "pipelines" themselves we can $limit e...
Replacing .NET WebBrowser control with a better browser, like Chrome?
...mulationCode = BrowserEmulationVersion.Version11
Else
Select Case ieVersion
Case 10
emulationCode = BrowserEmulationVersion.Version10
Case 9
emulationCode = BrowserEmulationVersion.Version9
C...
Explicitly calling return in a function or not
...son for not using explicit return. The following plot is created from data selected this way:
bench_nor2 <- function(x,repeats) { system.time(rep(
# without explicit return
(function(x) vector(length=x,mode="numeric"))(x)
,repeats)) }
bench_ret2 <- function(x,repeats) { system.time(rep(
# wi...
Natural Sort Order in C#
...haNumeric<T>(this IEnumerable<T> source, Func<T, string> selector)
{
int max = source
.SelectMany(i => Regex.Matches(selector(i), @"\d+").Cast<Match>().Select(m => (int?)m.Value.Length))
.Max() ?? 0;
return source.OrderBy(i => Regex.Replace(s...
How does database indexing work? [closed]
...arising from the file systems size limits, careful thought must be used to select the correct fields to index.
Since indices are only used to speed up the searching for a matching field within the records, it stands to reason that indexing fields used only for output would be simply a waste of disk...
Error in finding last used cell in Excel with VBA
...ad data? You will end up reaching the last row in the worksheet! It's like selecting cell A1 and then pressing End key and then pressing Down Arrow key. This will also give you unreliable results if there are blank cells in a range.
CountA is also unreliable because it will give you incorrect resul...
What is the difference between partitioning and bucketing a table in Hive ?
...
Interesting, I agree w.r.t the usage in select query. But wondered why people are using clustered by and sorted by together in table creation statement. If there is no significance to SORTED BY in DDL, then why this keyword is present? Didnt get that.
...
Proper use of the IDisposable interface
...never be cleaned up. The garbage collector doesn't know how to call DeleteHandle() on a variable of type IntPtr, it doesn't know whether or not it needs to call DeleteHandle().
Note: What is an unmanaged resource? If you found it in the Microsoft .NET Framework: it's managed. If you went poking ...
Cmake vs make sample codes?
... on your system configuration. Second, you perform the actual build in the selected build system.
Sources and build instructions are available at https://github.com/rhoelzel/make_cmake.
share
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im...
Why Qt is misusing model/view terminology?
...t provides simple views for their models. They have a controller built in: selecting, editing and moving items are something what in most cases a controller "controls". That is, interpreting user input (mouse clicks and moves) and giving the appropriate commands to the model.
Qt's models are indeed...