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How important is the order of columns in indexes?
...mns involved.
Giving that rationale, the only difference is comparing two 'strings' that differ earlier versus later in the string. This is a tiny part of the total cost. There is no "first pass / second pass", as mentioned in one Answer.
So, what order should be used?
Start with column(s) tested...
Using async/await for multiple tasks
...read.CurrentThread.ManagedThreadId, (workerStart-testStart).TotalSeconds.ToString("F2"));
await Task.Run(() => Thread.Sleep(SleepTimeout));
var workerEnd = DateTime.Now;
Console.WriteLine("Worker {0} stopped; the worker took {1} seconds, and it fini...
What are good examples of genetic algorithms/genetic programming solutions? [closed]
...e application started with a population of randomly-generated fixed-length strings (the "gene" part), each of which corresponded to a specific shape in the minute-by-minute price data of the S&P500 futures, as well as a specific order (buy or sell) and stop-loss and stop-profit amounts. Each st...
Python read-only property
...m 1: classes thus decorated all end up with an identical __name__, and the string representation of their type is homogenized as well. Problem 2: this decoration overwrites any custom __setattr__. Problem 3: users can defeat this with del MyClass.__setattr__.
– TigerhawkT3
...
val-mutable versus var-immutable in Scala
...collection.mutable.ArrayBuffer
object MyObject {
def main(args: Array[String]) {
val a = ArrayBuffer(1,2,3,4)
silly(a)
println(a) // a has been modified here
}
def silly(a: ArrayBuffer[Int]): Unit = {
a += 10
println(s"length: ${a.length}")
...
Most efficient way of making an if-elif-elif-else statement when the else is done the most?
...for 'this', 'that', and 'there' - and then comparing hash codes instead of strings. That turned out to be twice as slow as the original, so it looks like string comparisons are already pretty well optimised internally.
– foz
Jun 18 '13 at 16:23
...
Patterns for handling batch operations in REST web services?
... if (this.isCommand(cmd))
{
data += cmd.toRequestString();
this.sent[cmd.id] = cmd;
// ... and then send the contents of data in a POST request
}
}
}
That ought to get you going. Good luck!
...
mongoose vs mongodb (nodejs modules/extensions), which better? and why?
...mething like mongooseInstace.model('MyCollection', { "_id": Number, "xyz": String }) it's better to do (even though the collection name is really MyCollection): mongooseInstace.model('mycollection', { "_id": Number, "xyz": String })
But honestly, it's really useful. The biggest issue is the docume...
Basic example of using .ajax() with JSONP?
...ment that looks like this after it loads the data:
<script>
{['some string 1', 'some data', 'whatever data']}
</script>
However this is a bit inconvenient, because we have to fetch this array from script tag. So JSONP creators decided that this will work better (and it is):
script = ...
How do servlets work? Instantiation, sessions, shared variables and multithreading
...of the information about the HTTP request, such as its URL, headers, query string and body. The response object provides the ability to control and send the HTTP response the way you want by, for instance, allowing you to set the headers and the body (usually with generated HTML content from a JSP f...