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What's the difference between django OneToOneField and ForeignKey?
...)
>>> e2 = Engine2.objects.get(name='Wankel')
>>> e2.car2_set.all()
[<Car2: Mazda>]
Model Code
from django.db import models
class Engine(models.Model):
name = models.CharField(max_length=25)
def __unicode__(self):
return self.name
class Car(models.Model)...
How to change the CHARACTER SET (and COLLATION) throughout a database?
...
change database collation:
ALTER DATABASE <database_name> CHARACTER SET utf8 COLLATE utf8mb4_0900_ai_ci;
change table collation:
ALTER TABLE <table_name> CONVERT TO CHARACTER SET utf8 COLLATE utf8mb4_0900_ai_ci;
change column collation:
ALTER TABLE <table_name&g...
Printing without newline (print 'a',) prints a space, how to remove?
... you to set an end parameter. You can use it in >=2.6 by importing from __future__. I'd avoid this in any serious 2.x code though, as it will be a little confusing for those who have never used 3.x. However, it should give you a taste of some of the goodness 3.x brings.
>>> from __futur...
Remove multiple elements from array in Javascript/jQuery
...
jsfiddler - Error 404. We're truly sorry, but there is no such page.
– Ash
Jun 9 '17 at 14:07
add a comment
...
Getting mouse position in c#
... POINT lpPoint;
GetCursorPos(out lpPoint);
// NOTE: If you need error handling
// bool success = GetCursorPos(out lpPoint);
// if (!success)
return lpPoint;
}
share
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Removing index column in pandas when reading a csv
...o_sql("table",cursor,if_exists="append",index=False) also fixes the sqlite error sqlite3.OperationalError: table message has no column named index
– Anna
Jun 3 '18 at 0:55
2
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Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
...ng the ZIP implementation would like to access the data directly):
struct __attribute__((__packed__)) LocalFileHeader {
uint32_t signature;
uint16_t minVersion, flag, method, modTime, modDate;
uint32_t crc32, compressedSize, uncompressedSize;
uint16_t nameLength, extraLength;
};
T...
Saving an Object (Data persistence)
...tion of it to your example:
import pickle
class Company(object):
def __init__(self, name, value):
self.name = name
self.value = value
with open('company_data.pkl', 'wb') as output:
company1 = Company('banana', 40)
pickle.dump(company1, output, pickle.HIGHEST_PROTOCOL)
...
Store a closure as a variable in Swift
... can be declared as typealias as below
typealias Completion = (Bool, Any, Error) -> Void
If you want to use in your function anywhere in code; you can write like normal variable
func xyz(with param1: String, completion: Completion) {
}
...
Getting number of elements in an iterator in Python
...d work:
>>> iter = (i for i in range(50))
>>> sum(1 for _ in iter)
50
Although it does iterate through each item and count them, it is the fastest way to do so.
It also works for when the iterator has no item:
>>> sum(1 for _ in range(0))
0
Of course, it runs foreve...