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How do MySQL indexes work?
...index type is the B+Tree based index, that stores the elements in a sorted order. Also, you don't have to access the real table to get the indexed values, which makes your query return way faster.
The "problem" about this index type is that you have to query for the leftmost value to use the index....
Android: How can I get the current foreground activity (from a service)?
... the service call an event method on that callback/listener object
Send an ordered broadcast Intent to the activity, with a low-priority BroadcastReceiver as backup (to raise a Notification if the activity is not on-screen) -- here is a blog post with more on this pattern
...
How to concatenate text from multiple rows into a single text string in SQL server?
...ts ST1
WHERE ST1.SubjectID = ST2.SubjectID
ORDER BY ST1.SubjectID
FOR XML PATH ('')
) [Students]
FROM dbo.Students ST2
) [Main]
You can do the same thing in a more compact way if you can concat the commas at the beginning and ...
What does O(log n) mean exactly?
...rinter's office, and our phone book had all its pages inserted in a random order. Fix the ordering so that it's correct by looking at the first name on each page and then putting that page in the appropriate spot in a new, empty phone book.
For the below examples, we're now at the printer's office...
Storing time-series data, relational or non?
...has to handle ~3 million measures with a 1 minute frequency? How would you order the PK for such a table? Wouldn't Device, Metric, DateTime create fragmentation and force the RDBMS to lots of page split? Instead putting DateTime first would reduce fragmentation (I'm assuming time ordered inserts) bu...
What are Maven goals and phases and what is their difference?
...
Goals are executed in phases which help determine the order goals get executed in. The best understanding of this is to look at the default Maven lifecycle bindings which shows which goals get run in which phases by default. The compile phase goals will always be executed befo...
scanf() leaves the new line char in the buffer
...scanf terminology) other than conversions, like the literal text in scanf("order = %d", &order); doesn't skip whitespace either. The literal order has to match the next character to be read.
So you probably want " order = %d" there if you want to skip a newline from the previous line but still...
Shuffle an array with python, randomize array item order with python
What's the easiest way to shuffle an array with python?
11 Answers
11
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JavaScript for…in vs for
...u use for in to loop over property names in an object, the results are not ordered. Worse: You might get unexpected results; it includes members inherited from the prototype chain and the name of methods.
Everything but the properties can be filtered out with .hasOwnProperty. This code sample does ...
How to move an iFrame in the DOM without losing its state?
...The basic idea is to create a flex-box wrapper and then define an specific order for the iframes using the order attribute on each iframe wrapper.
<style>
.container{
display: flex;
flex-direction: column;
}
</style>
<div class="container">
<div id="wrap1" style="...