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SET versus SELECT when assigning variables?
...ed then SET will assign NULL, where SELECT will not make the assignment at all (so the variable will not be changed from its previous value)
As far as speed differences - there are no direct differences between SET and SELECT. However SELECT's ability to make multiple assignments in one shot does ...
How to make a chain of function decorators?
...her object
scream = shout
# Notice we don't use parentheses: we are not calling the function,
# we are putting the function "shout" into the variable "scream".
# It means you can then call "shout" from "scream":
print(scream())
# outputs : 'Yes!'
# More than that, it means you can remove the old...
How to put a unicode character in XAML?
...
Markup files that are created in Microsoft Visual Studio are
automatically saved in the Unicode UTF-8 file format, which means that
most special characters, such as accent marks, are encoded correctly.
However, there is a set of commonly-used special characters that are
handled differentl...
What's the difference between “groups” and “captures” in .NET regular expressions?
...hat
each Group object contains a
collection of Captures representing
all the intermediary matches by the
group during the match, as well as the
final text matched by the group.
And a few pages later, this is his conclusion:
After getting past the .NET
documentation and actually
...
docker mounting volumes on host
...independent of the container's life cycle. Docker therefore never automatically delete volumes when you remove a container, nor will it "garbage collect" volumes that are no longer referenced by a container." One of these statements must be wrong.
– mc0e
May 6...
how does array[100] = {0} set the entire array to 0?
...se an empty initializer list, causing the compiler to aggregate-initialize all of the elements of the array:
char array[100] = {};
As for what sort of code the compiler might generate when you do this, take a look at this question: Strange assembly from array 0-initialization
...
MySQL foreign key constraints, cascade delete
...#2 (blue):
DELETE FROM categories WHERE (id = 2);
the DBMS will look at all the tables which have a foreign key pointing at the 'categories' table, and delete the records where the matching id is 2. Since we only defined the foreign key relationship in products_categories, you end up with this ta...
What is the difference between related SQLite data-types like INT, INTEGER, SMALLINT and TINYINT?
When creating a table in SQLite3, I get confused when confronted with all the possible datatypes which imply similar contents, so could anyone tell me the difference between the following data-types?
...
How exactly does the python any() function work?
...st of some items. If it contained [0, False, '', 0.0, [], {}, None] (which all have boolean values of False) then any(lst) would be False. If lst also contained any of the following [-1, True, "X", 0.00001] (all of which evaluate to True) then any(lst) would be True.
In the code you posted, x > ...
What do commas and spaces in multiple classes mean in CSS?
..._12 .grid_6,
.container_16 .grid_8 {
width: 460px;
}
That says "make all .grid_6's within .container_12's and all .grid_8's within .container_16's 460 pixels wide." So both of the following will render the same:
<div class="container_12">
<div class="grid_6">460px Wide</div&g...