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Quicksort vs heapsort
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For any deterministic, constant time pivot selection strategy, you can find an array that produces the O(n^2) worst case. It's not enough to eliminate just the minimum. You have to reliably chose pivots that are within a certain pecrentile band.
–...
Is a view faster than a simple query?
...e the indexed view directly, or, more importantly, the query optimizer can select the view if it determines that the view can be substituted for some or all of the query in the lowest-cost query plan. In the second case, the indexed view is used instead of the underlying tables and their ordinary in...
SQL, Postgres OIDs, What are they and why are they useful?
...ned system column oid will no longer be invisible by default. Performing a SELECT * will now include this column. Note that this extra “surprise” column may break naïvely written SQL code.
share
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Using TortoiseSVN how do I merge changes from the trunk to a branch and vice versa?
...rge Type: Merge a range of revisions | Click 'Next'
Merge revision range: Select the URL of the trunk directory that you copied to the branch / tag. Enter the revisions to merge or leave the field empty to merge all revisions | click 'Next'
Merge options: I just left these as default | click 'Merg...
Is there an Eclipse line-width marker?
...ou have to set it in the formatter: From menu [Window]-->[Preferences], select [Java]-->[Code Style]-->[Formatter], and then edit your formatter profile. In the tab page [Line wrapping], you can find a setting named "Maximum line width". Change this setting, and the print margin in Java sou...
How to have an auto incrementing version number (Visual Studio)? [duplicate]
...item” for each projects, navigate to the folder with T4
template file, select corresponding “.cs” file and add it as a link.
That will do!
What I like about this approach is that it is lightweight (no custom
MsBuild tasks), and auto-generated version information is not added to
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What is the difference between CascadeType.REMOVE and orphanRemoval in JPA?
... and remove the post entity:
Post post = entityManager.createQuery("""
select p
from Post p
join fetch p.comments
where p.id = :id
""", Post.class)
.setParameter("id", postId)
.getSingleResult();
entityManager.remove(post);
Hibernate is going to execute three delete statements:...
Drawing an image from a data URL to a canvas
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in javascript , using jquery for canvas id selection :
var Canvas2 = $("#canvas2")[0];
var Context2 = Canvas2.getContext("2d");
var image = new Image();
image.src = "images/eye.jpg";
Context2.drawImage(image, 0, 0);
html5:
<canv...
Path of assets in CSS files in Symfony 2
...css, b.css, c.css, etc: all identical, just changing the color and the CSS selector.
.a
{
background: red url('../images/devil.png');
}
The "directories" structure is:
Directories
All this came, because I did not want the individual original files exposed to the public, specially if I want...
Good MapReduce examples [closed]
...erations that you can do in MapReduce is the set of normal SQL operations: SELECT, SELECT WHERE, GROUP BY, ect.
Another good example is matrix multiply, where you pass one row of M and the entire vector x and compute one element of M * x.
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