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ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
Why am I getting this database error when I update a table?
14 Answers
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MySQL Results as comma separated list
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You can use GROUP_CONCAT to perform that, e.g. something like
SELECT p.id, p.name, GROUP_CONCAT(s.name) AS site_list
FROM sites s
INNER JOIN publications p ON(s.id = p.site_id)
GROUP BY p.id, p.name;
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How do I convert a String object into a Hash object?
I have a string which looks like a hash:
13 Answers
13
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How to reshape data from long to wide format
I'm having trouble rearranging the following data frame:
11 Answers
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How to access a preexisting collection with Mongoose?
I have a large collection of 300 question objects in a database test . I can interact with this collection easily through MongoDB's interactive shell; however, when I try to get the collection through Mongoose in an express.js application I get an empty array.
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Create singleton using GCD's dispatch_once in Objective-C
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This is a perfectly acceptable and thread-safe way to create an instance of your class. It may not technically be a "singleton" (in that there can only ever be 1 of these objects), but as long as you only use the [Foo sharedFoo] method to access the object, this is good enough.
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Django : How can I see a list of urlpatterns?
How can I see the current urlpatterns that "reverse" is looking in?
16 Answers
16
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Best practice to return errors in ASP.NET Web API
...I usually send back an HttpResponseException and set the status code accordingly depending on the exception thrown and if the exception is fatal or not will determine whether I send back the HttpResponseException immediately.
At the end of the day it's an API sending back responses and not views, s...
Javascript - Append HTML to container element without innerHTML
I need a way to append HTML to a container element without using innerHTML. The reason why I do not want to use innerHTML is because when it is use like this:
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An item with the same key has already been added
... get this error whenever I submit the form also the action method is not being called because of this:
21 Answers
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