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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)...
Difference between / and /* in servlet mapping url pattern
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<url-pattern></url-pattern> throws an error: Invalid <url-pattern> in servlet mapping
– slim
Jan 18 '16 at 17:10
...
Check whether a cell contains a substring
...
got an error using , instead of ;. After changing the provided formula to =ISNUMBER(SEARCH("Some Text"; A3)) it worked. Thanks!
– renatov
Apr 22 '15 at 19:18
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How to change the CHARACTER SET (and COLLATION) throughout a database?
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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...
When to use virtual destructors?
...would it make sense to have the compiler check this condition and issue an error is it is not satisfied?
– Giorgio
May 6 '12 at 9:29
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How do I capture response of form.submit
...er responded with: " + event.target.response); // raw response
};
// or onerror, onabort
var formData = new FormData(document.getElementById("myForm"));
xhr.send(formData);
For POST's the default content type is "application/x-www-form-urlencoded" which matches what we're sending in the above sn...
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...
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)
...
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...
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...