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How to upload a file in Django? [closed]
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Phew, Django documentation really does not have good example about this. I spent over 2 hours to dig up all the pieces to understand how this works. With that knowledge I implemented a project that makes possible to upload files and show them as list. To...
Any way to exit bash script, but not quitting the terminal
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You can add an extra exit command after the return statement/command so that it works for both, executing the script from the command line and sourcing from the terminal.
Example exit code in the script:
if [ $# -lt 2 ]; then
echo...
SQL Server Index Naming Conventions [closed]
...ems that the primary key index is named PK_ and non-clustered indexes typically start with IX_. Are there any naming conventions beyond that for unique indexes?
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MongoDB: How to update multiple documents with a single command?
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How to do it for oldvalue+"some string"
– Mahesh K
Nov 14 '17 at 11:03
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What's the difference between :: (double colon) and -> (arrow) in PHP?
... used to access static members, such usage is discouraged), while :: is usually used to access static members (though in a few special cases, it's used to access instance members).
In general, :: is used for scope resolution, and it may have either a class name, parent, self, or (in PHP 5.3) static...
UIButton Image + Text IOS
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I see very complicated answers, all of them using code. However, if you are using Interface Builder, there is a very easy way to do this:
Select the button and set a title and an image. Note that if you set the background instead of the image then the ima...
ModelSerializer using model property
... Meta is optional. If you omit fields, in the above example, you would get all the MyModel fields plus ext_link in the serialized data. And this is really awesome for complex models! EDIT: At least, this is true for djangorestframework==2.3.14.
– e.thompsy
Feb ...
Timing a command's execution in PowerShell
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function time {
Param(
[Parameter(Mandatory=$true)]
[string]$command,
[switch]$quiet = $false
)
$start = Get-Date
try {
if ( -not $quiet ) {
iex $command | Write-Host
} else {
iex $command > $null
}
} fi...
What is the difference between Ruby 1.8 and Ruby 1.9
...ements do not introduce scope in Ruby.
What's changed?
Single character strings.
Ruby 1.9
irb(main):001:0> ?c
=> "c"
Ruby 1.8.6
irb(main):001:0> ?c
=> 99
String index.
Ruby 1.9
irb(main):001:0> "cat"[1]
=> "a"
Ruby 1.8.6
irb(main):001:0> "cat"[1]
=> 97
{"...
List all sequences in a Postgres db 8.1 with SQL
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The following query gives names of all sequences.
SELECT c.relname FROM pg_class c WHERE c.relkind = 'S';
Typically a sequence is named as ${table}_id_seq. Simple regex pattern matching will give you the table name.
To get last value of a sequence use the ...