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How to think in data stores instead of databases?
...nk 100% in object relationships that map directly to table structures, and now it's hard to see anything differently. I can understand some of the benefits of Google Datastore (e.g. performance and the ability to distribute data), but some good database functionality is sacrificed (e.g. joins).
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How do I output an ISO 8601 formatted string in JavaScript?
...ose function calls like "getUTCFullYear" are failing because they are not known to IE document mode 5.
– Elaskanator
Mar 5 '18 at 16:25
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sh...
What is the difference between typeof and instanceof and when should one be used vs. the other?
... instanceof Object returns false, and doesn't throw an exception. I don't know how recent that change is, but it makes instanceof more appealing.
– Cypress Frankenfeld
Jun 26 '13 at 16:01
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Django “xxxxxx Object” display customization in admin action sidebar
...Actions log wasn't showing up the names after I set unicode - I should of known it was just a log stored in the db taking data at the time of creation!
– markwalker_
Sep 11 '12 at 10:45
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Regular expression to allow spaces between words
...tl;dr
Just add a space in your character class.
^[a-zA-Z0-9_ ]*$
Now, if you want to be strict...
The above isn't exactly correct. Due to the fact that * means zero or more, it would match all of the following cases that one would not usually mean to match:
An empty string, "".
A string...
How can I generate a unique ID in Python? [duplicate]
...uction code (and about to roll out to more uses of it in a newer release). Now I'm scared!
– Matthew Schinckel
Nov 6 '10 at 7:38
2
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Expand a random range from 1–5 to 1–7
... sampling, e.g.:
int i;
do
{
i = 5 * (rand5() - 1) + rand5(); // i is now uniformly random between 1 and 25
} while(i > 21);
// i is now uniformly random between 1 and 21
return i % 7 + 1; // result is now uniformly random between 1 and 7
This has an expected runtime of 25/21 = 1.19 itera...
How to elegantly ignore some return values of a MATLAB function?
...ction:
Func3 = @() deal(1,2,3);
[a,b,c]=Func3();
% yields a=1, b=2, c=3
Now the key here is that if you use an variable twice in the left hand side of a multiple-expression assignment, an earlier assignment is clobbered by the later assignment:
[b,b,c]=Func3();
% yields b=2, c=3
[c,c,c]=Func3()...
Is there a REAL performance difference between INT and VARCHAR primary keys?
... your database? And pretend that SU never exists? And all references to SU now points to Russia?
– Dainius
Aug 23 '12 at 8:01
6
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“is” operator behaves unexpectedly with integers
...
does anyone know how that range (-5, 256) was chosen? i wouldn't be too surprised if it were (0, 255) or even (-255, 255), but a range of 262 numbers starting at -5 seems surprisingly arbitrary.
– Woodrow Barlow
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