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How to limit the maximum value of a numeric field in a Django model?
...as various numeric fields available for use in models, e.g. DecimalField and PositiveIntegerField . Although the former can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a certain ...
How to concatenate columns in a Postgres SELECT?
I have two string columns a and b in a table foo .
8 Answers
8
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Maximum number of records in a MySQL database table
...utoincrement field. What would happen if I add milions of records? How to handle this kind of situations?
Thx!
8 Answers
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Count the items from a IEnumerable without iterating?
Let's say I want iterate on those and write something like processing #n of #m.
19 Answers
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Python argparse mutual exclusive group
...ns within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
prog
command 1
-a: ...
command 2
-b: ...
-c: ...
To invoke with the first set of arguments:
prog command_1 -a xxxx
To invoke with the sec...
In Hibernate Validator 4.1+, what is the difference between @NotNull, @NotEmpty, and @NotBlank?
....
@NotEmpty: The CharSequence, Collection, Map or Array object is not null and size > 0.
@NotBlank: The string is not null and the trimmed length is greater than zero.
To help you understand, let's look into how these constraints are defined and carried out (I'm using version 4.1):
The @Not...
How to manage client-side JavaScript dependencies? [closed]
... |___ require.js
main.js is where you initialize your client application and configure require.js:
require.config({
baseUrl: "/sampleapp",
paths: {
jquery: "libs/jquery", // Local
underscore: "http://underscorejs.org/underscore-min.js", // Remote
backbone: "https:/...
How do I move a file (or folder) from one folder to another in TortoiseSVN?
...er within the same repository without having to use Repo Browser to do it, and without creating two independent add/delete operations. Using Repo Browser works fine except that your code will be hanging in a broken state until you get any supporting changes checked in afterwards (like the .csproj f...
What's the difference between Perl's backticks, system, and exec?
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exec
executes a command and never returns.
It's like a return statement in a function.
If the command is not found exec returns false.
It never returns true, because if the command is found it never returns at all.
There is also no point ...
What is the difference between a generative and a discriminative algorithm?
Please, help me understand the difference between a generative and a
discriminative algorithm, keeping in mind that I am just a beginner.
...