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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... NULL is less efficient
In PostgreSQL, NOT IN is less efficient
In Oracle, all three methods are the same.
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Retina displays, high-res background images
...ges/box-bg@2x.png') no-repeat top left / 200px 200px;
}
However, I personally would not advise using the shorthand form as it is not supported in iOS <= 6 or Android making it unreliable in most situations.
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PostgreSQL - max number of parameters in “IN” clause?
...ArrayOpExpr from IN/NOT IN, but this is only
* possible if the inputs are all scalars (no RowExprs) and there is a
* suitable array type available. If not, we fall back to a boolean
* condition tree with multiple copies of the lefthand expression.
* Also, any IN-list items that contain Vars are...
Is REST DELETE really idempotent?
...ce refers to the state of the system after the request has completed
In all cases (apart from the error issues - see below), the account no longer exists.
From here
"Methods can also have the property of
"idempotence" in that (aside from
error or expiration issues) the
side-effects of...
Unable to type in Visual Studio
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Simply delete your all temp file from temp folder.
Note: Before delete temp file close visual studio.
To delete temp files:
Open Run window by pressing Windows button + R
Type %temp% in the text box.
Press enter
Run window image
Now you ...
UITableView set to static cells. Is it possible to hide some of the cells programmatically?
...imated:YES];
Note to always use only (reloadDataAnimated:YES/NO)
(dont call [self.tableView reloadData] directly)
This doesn't use the hacky solution with setting height to 0 and allows you to animate the change and hide whole sections
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MySQL 'create schema' and 'create database' - Is there any difference
... CREATE SCHEMA is a synonym for CREATE DATABASE as of MySQL 5.0.2.
this all goes back to an ANSI standard for SQL in the mid-80s.
That standard had a "CREATE SCHEMA" command, and it served to introduce
multiple name spaces for table and view names. All tables and views were
created within a "s...
Intelligent point label placement in R
...implement INTELLIGENT label placement in R plot? I tried some but they are all problematic - many labels are overlaping either each other or other points (or other objects in the plot, but I see that this is much harder to handle).
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How to create a directory using Ansible
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If state=directory, all immediate subdirectories will be created if they do not exist, since 1.7 they will be created with the supplied permissions.
– Alex
Oct 6 '16 at 10:05
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How can I multiply all items in a list together with Python?
...m together. Example:
[1,2,3,4,5,6] will give me 1*2*3*4*5*6 . I could really use your help.
17 Answers
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