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Why are Oracle table/column/index names limited to 30 characters?
..., but there is always a case that turns up where we hit this limit - especially in naming foreign keys.
10 Answers
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Correct way to use get_or_create?
...f the fields have to be included in defaults. In case CREATE event occurs, all the fields are taken into consideration.
It looks like you need to be returning into a tuple, instead of a single variable, do like this:
customer.source,created = Source.objects.get_or_create(name="Website")
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Is there a Mutex in Java?
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edited Nov 11 '12 at 16:42
answered Mar 13 '11 at 17:25
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Neo4j - Cypher vs Gremlin query language
...her the engine tries to find the best traversing solution itself.
I personally use Cypher because of its simplicity and, to date, I have not had any situations where I had to use Gremlin (except working with Gremlin graphML import/export functions). I expect, however, that even if i would need to u...
Detect if the app was launched/opened from a push notification
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I am getting the call to application:didReceiveRemoteNotification: after tapping the notification regardless of whether the app is just in the background or not running at all so this answer suits my needs perfectly. Tested on iOS 7 & 8
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Making an array of integers in iOS
...rays are such a hassle for anything but trivial, one-off use that it's actually less trouble to wrap any arrays you plan on keeping around as NSArrays of NSNumber.
– Chuck
Jul 27 '10 at 1:58
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How to write file if parent folder doesn't exist?
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If the whole path already exists, mkdirp is a noop. Otherwise it creates all missing directories for you.
This module does what you want: https://npmjs.org/package/writefile . Got it when googling for "writefile mkdirp". This module returns a promise instead of taking a callback, so be sure to r...
How to install JSTL? The absolute uri: http://java.sun.com/jstl/core cannot be resolved
... deployed with this application
That URI is for JSTL 1.0, but you're actually using JSTL 1.2 which uses URIs with an additional /jsp path (because JSTL, who invented EL expressions, was since version 1.1 integrated as part of JSP in order to share/reuse the EL logic in plain JSP too).
So, fix the...
The difference between fork(), vfork(), exec() and clone()
...d I expected there to be a huge amount of information on this, but there really wasn't any solid comparison between the four calls.
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Control cannot fall through from one case label
...is present. I have the following code. But I am getting a "Control cannot fall through from one case label" error.
8 Answer...