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Set value to NULL in MySQL
... can be inserted/updated without quotes:
INSERT INTO user (name, something_optional) VALUES ("Joe", NULL);
UPDATE user SET something_optional = NULL;
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MySQL Fire Trigger for both Insert and Update
...me.
1. Define the INSERT trigger:
DELIMITER //
DROP TRIGGER IF EXISTS my_insert_trigger//
CREATE DEFINER=root@localhost TRIGGER my_insert_trigger
AFTER INSERT ON `table`
FOR EACH ROW
BEGIN
-- Call the common procedure ran if there is an INSERT or UPDATE on `table`
-- NEW.id is an...
How can I scale an image in a CSS sprite
...alt="" src="spacer.png">
<img class="sprite" alt="icon" src="sprite_800x160.jpg">
</a>
<a class="stretchy s2" href="#">
<img class="spacer" alt="" src="spacer.png">
<img class="sprite" alt="icon" src="sprite_800x160.jpg">
</a>
<a class="stretchy s3" hr...
How do I find numeric columns in Pandas?
...
You could use select_dtypes method of DataFrame. It includes two parameters include and exclude. So isNumeric would look like:
numerics = ['int16', 'int32', 'int64', 'float16', 'float32', 'float64']
newdf = df.select_dtypes(include=numerics)
...
Label encoding across multiple columns in scikit-learn
...
You can easily do this though,
df.apply(LabelEncoder().fit_transform)
EDIT2:
In scikit-learn 0.20, the recommended way is
OneHotEncoder().fit_transform(df)
as the OneHotEncoder now supports string input.
Applying OneHotEncoder only to certain columns is possible with the Colum...
Should I use encodeURI or encodeURIComponent for encoding URLs?
...
Here is a summary.
escape() will not encode @ * _ + - . /
Do not use it.
encodeURI() will not encode A-Z a-z 0-9 ; , / ? : @ & = + $ - _ . ! ~ * ' ( ) #
Use it when your input is a complete URL like 'https://searchexample.com/search?q=wiki'
encodeURIComponent() will ...
How do I add the contents of an iterable to a set?
...rt Timer
a = set(range(1, 100000))
b = list(range(50000, 150000))
def one_by_one(s, l):
for i in l:
s.add(i)
def cast_to_list_and_back(s, l):
s = set(list(s) + l)
def update_set(s,l):
s.update(l)
results are:
one_by_one 10.184448844986036
cast_to_list_and_back 7.96925...
How can I alter a primary key constraint using SQL syntax?
...the constraint with an Alter table then recreate it.
ALTER TABLE <Table_Name>
DROP CONSTRAINT <constraint_name>
ALTER TABLE <Table_Name>
ADD CONSTRAINT <constraint_name> PRIMARY KEY (<Column1>,<Column2>)
...
Suppress/ print without b' prefix for bytes in Python 3
...
If we take a look at the source for bytes.__repr__, it looks as if the b'' is baked into the method.
The most obvious workaround is to manually slice off the b'' from the resulting repr():
>>> x = b'\x01\x02\x03\x04'
>>> print(repr(x))
b'\x01\x02...
How do I add multiple arguments to my custom template filter in a django template?
...[1,2,3,4] you will want a template filter that looks like this:
{% if X|is_in:"1,2,3,4" %}
Now we can create your templatetag like this:
from django.template import Library
register = Library()
def is_in(var, args):
if args is None:
return False
arg_list = [arg.strip() for arg ...