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Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
...ur question. If you click on the link you will see the reasons those users selected.
– Aaron Bertrand
Jun 23 '12 at 17:13
...
iOS change navigation bar title font and color
...answers. I'm just sharing the storyboard version for setting the font.
1. Select Your Navigation Bar within your Navigation Controller
2. Change the Title Font in the Attributes Inspector
(You will likely need to toggle the Bar Tint for the Navigation Bar before Xcode picks up the new font)
...
MySQL 'create schema' and 'create database' - Is there any difference
...asn't been allocated to any particular schema, you can do something like:
SELECT *
FROM your_table
which is equivalent to:
SELECT *
FROM dbo.your_table
Now, SQL server allows the creation of different schema, which gives you the possibility of grouping tables that share a similar purpose. That...
How do I check/uncheck all checkboxes with a button using jQuery?
...ecking/unchecking the parent checkbox all the child checkboxes are getting selected/deselected also with the text of parent checkbox getting changed to checkall/uncheckall.
...
Can I have an onclick effect in CSS?
...active too but is not listed because it does not support some of the other selectors)
– jrajav
Nov 29 '12 at 16:43
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How to find the kth largest element in an unsorted array of length n in O(n)?
...h order statistic. There's a very simple randomized algorithm (called quickselect) taking O(n) average time, O(n^2) worst case time, and a pretty complicated non-randomized algorithm (called introselect) taking O(n) worst case time. There's some info on Wikipedia, but it's not very good.
Everything...
Parallel foreach with asynchronous lambda
...is:
var bag = new ConcurrentBag<object>();
var tasks = myCollection.Select(async item =>
{
// some pre stuff
var response = await GetData(item);
bag.Add(response);
// some post stuff
});
await Task.WhenAll(tasks);
var count = bag.Count;
If you need something more complex, check o...
Django filter queryset __in for *every* item in list
...query:
In [17]: print Photo.objects.filter(tags=t1).filter(tags=t2).query
SELECT "test_photo"."id"
FROM "test_photo"
INNER JOIN "test_photo_tags" ON ("test_photo"."id" = "test_photo_tags"."photo_id")
INNER JOIN "test_photo_tags" T4 ON ("test_photo"."id" = T4."photo_id")
WHERE ("test_photo_tags"."ta...
When to use a View instead of a Table?
...
Oh there are many differences you will need to consider
Views for selection:
Views provide abstraction over tables. You can add/remove fields easily in a view without modifying your underlying schema
Views can model complex joins easily.
Views can hide database-specific stuff from you. E....
Compare two DataFrames and output their differences side-by-side
...
Is it possible to select only different rows? In this case how do I select second and third row without selecting first row (111)?
– shantanuo
May 4 '18 at 8:13
...