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How to upload a file in Django? [closed]
...e Django stores uploaded files and from what URL Django serves them. MEDIA_ROOT and MEDIA_URL are in settings.py by default but they are empty. See the first lines in Django Managing Files for details. Remember also set the database and add myapp to INSTALLED_APPS
...
import os
BASE_DIR = os.path....
Sqlite LIMIT / OFFSET query
...T <count> OFFSET <skip>
It's compatible with the syntax from MySQL and PostgreSQL. MySQL supports both syntax forms, and its docs claim that the second syntax with OFFSET was meant to provide compatibility with PostgreSQL. PostgreSQL docs show it only supports the second syntax, and ...
In Docker, what's the difference between a container and an image? [duplicate]
...o give us an interactive bash shell.
$ docker run -i -t ubuntu /bin/bash
root@48cff2e9be75:/# ls
bin boot dev etc home lib lib64 media mnt opt proc root run sbin srv sys tmp usr var
root@48cff2e9be75:/# cat > foo
This is a really important file!!!!
root@48cff2e9be75:/# exit
...
ASP.NET MVC Relative Paths
...IPT/>, <LINK/>, and as a result the tilde no longer maps to
the root directory.
For example, if you rewrite requests for asp.net/content to asp.net,
the href attribute in
<A href="~/content/"/> resolves to
/content/content/ instead of /. To suppress this change, you can ...
String concatenation does not work in SQLite
... ||
Oracle CONCAT(string1, string2) or ||
MySQL CONCAT(string1, string2, string3...) or || if PIPES_AS_CONCAT enabled
Postgres CONCAT(string1, string2, string3...) or ||
Microsoft SQL Server 2012+ CONCAT(string1, string2, str...
Can someone explain in simple terms to me what a directed acyclic graph is?
... Andriyev, +1 for the deadlock example. This is in fact used by MySQL's InnoDB engine, and they call it a "wait-for-graph", as in, "that row has to wait for the lock on that row to be released"
– Roland Bouman
Feb 17 '10 at 19:40
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How to do an update + join in PostgreSQL?
...
coming from mysql it's unintuitive that the same join used for select won't also update just by adding a set phrase :( still - the syntax for this is probably easier for a newcomer to sql to master.
– WEBjuju
...
How do I create a URL shortener?
...Take an auto-generated, unique numerical key (the auto-incremented id of a MySQL table for example).
For this example, I will use 12510 (125 with a base of 10).
Now you have to convert 12510 to X62 (base 62).
12510 = 2×621 + 1×620 = [2,1]
This requires the use of integer division and modulo. A ...
Include all existing fields and add new fields to document
...
You can use $$ROOT to references the root document. Keep all fields of this document in a field and try to get it after that (depending on your client system: Java, C++, ...)
[
{
$project: {
custom_field: "$obj.ob...
no acceptable C compiler found in $PATH when installing python
...lled or it's not in your $PATH variable.
To install gcc use this: (run as root)
Redhat base:
yum groupinstall "Development Tools"
Debian base:
apt-get install build-essential
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