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Foreign Key to non-primary key
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If you really want to create a foreign key to a non-primary key, it MUST be a column that has a unique constraint on it.
From Books Online:
A FOREIGN KEY constraint does not have to be linked only to a PRIMARY
KEY constraint in...
ADB No Devices Found
I am attempting to install an Android app on my brand new Nexus 10 . I have a .apk file. I have downloaded the Android SDK, installed "Android SDK Tools", "Android SDK Platform-tools", and Google USB Driver. I have checked the setting on my Nexus 10 for "Unknown Sources".
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How do I get a list of column names from a psycopg2 cursor?
... to generate column labels directly from the selected column names, and recall seeing that python's psycopg2 module supports this feature.
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Rails :include vs. :joins
...de functionality was changed with Rails 2.1. Rails used to do the join in all cases, but for performance reasons it was changed to use multiple queries in some circumstances. This blog post by Fabio Akita has some good information on the change (see the section entitled "Optimized Eager Loading")....
PHP - how to best determine if the current invocation is from CLI or web server?
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A small caveat about this method: it will not return "cli" when run from a cron job. There's a number od differents keys to choose from inside of $_SERVER to determine more reliably whether the request came via HTTP or not.
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Programmatically select text in a contenteditable HTML element?
In JavaScript, it's possible to programmatically select text in an input or textarea element. You can focus an input with ipt.focus() , and then select its contents with ipt.select() . You can even select a specific range with ipt.setSelectionRange(from,to) .
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Putty: Getting Server refused our key Error
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OK, there was a small typo in my key. Apparently when pasting to file the first letter was cut off and it started with sh-rsa instead of ssh-rsa.
nrathathaus - your answer was very helpful, thanks a lot, this answer is credited to you :) I di...
No line-break after a hyphen
...e break after a hyphen - on a case-by-case basis that is compatible with all browsers.
5 Answers
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Bash Templating: How to build configuration files from templates with Bash?
...\}/defined $ENV{$1} ? $ENV{$1} : $&/eg' < template.txt
to replace all ${...} strings with corresponding enviroment variables (do not forget to export them before running this script).
For pure bash this should work (assuming that variables do not contain ${...} strings):
#!/bin/bash
while...
Django rest framework, use different serializers in the same ModelViewSet
... like to provide two different serializers and yet be able to benefit from all the facilities of ModelViewSet :
6 Answers
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