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How to randomly select rows in SQL?
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SELECT TOP 5 Id, Name FROM customerNames
ORDER BY NEWID()
That said, everybody seems to come to this page for the more general answer to your question:
Selecting a random row in SQL
Select a random row with MySQL:
SELECT column FROM table
ORDER BY RAND()
LIMIT ...
When to use Preorder, Postorder, and Inorder Binary Search Tree Traversal strategies
...BST's plenty in my life, I've never even contemplated using anything but Inorder traversal (while I am aware of and know how easy it is to adapt a program to use pre/post-order traversal).
...
When NOT to call super() method when overriding?
....save() will perform the save() logic for both A and B, in this particular order. If you weren't calling super.save() inside B.save(), A.save() wouldn't be called. And if you called super.save() after save(b), A.save() would be effectively performed afterwards B.save().
If you want to override supe...
How to sort a list in Scala by two fields?
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@SachinK: you have to create your own Ordering for Row class and use it with sorted method like this: rows.sorted(customOrdering). You could also use custom Ordering for Tuple2 like this: rows.sortBy(r => (r.lastName, r.firstName))( Ordering.Tuple2(Ordering.St...
java.util.regex - importance of Pattern.compile()?
...d reset a Matcher object that is only ever used by one thread at a time in order to reduce allocations.
– AndrewF
Jul 3 '19 at 20:40
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show ...
Is async HttpClient from .Net 4.5 a bad choice for intensive load applications?
...ient, by default it will copy the network stream into a memory stream. In order to use HttpClient in the same way that you are currently using HttpWebRquest you would need to do
var requestMessage = new HttpRequestMessage() {RequestUri = URL};
Task<HttpResponseMessage> getTask = httpClient.S...
How does Python 2 compare string and int? Why do lists compare as greater than numbers, and tuples g
...ython implementation detail: Objects of different types except numbers are ordered by their type names; objects of the same types that don’t support proper comparison are ordered by their address.
When you order two strings or two numeric types the ordering is done in the expected way (lexicogra...
What's the $unwind operator in MongoDB?
...g and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what the use case that you are trying to quote is saying. The example document from mongodb.org is as follows:
{
title : "this is my ti...
Saving an Object (Data persistence)
...advantage is you don't need to know how many object instances are saved in order to load them back later (although doing so without that information is possible, it requires some slightly specialized code). See the answers to the related question Saving and loading multiple objects in pickle file? f...
The order of keys in dictionaries
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You could use OrderedDict (requires Python 2.7) or higher.
Also, note that OrderedDict({'a': 1, 'b':2, 'c':3}) won't work since the dict you create with {...} has already forgotten the order of the elements. Instead, you want to use Order...