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JPA getSingleResult() or null
I have an insertOrUpdate method which inserts an Entity when it doesn't exist or update it if it does. To enable this, I have to findByIdAndForeignKey , if it returned null insert if not then update. The problem is how do I check if it exists? So I tried getSingleResult . But it throws an ex...
Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
I want to extract just the date part from a timestamp in PostgreSQL.
7 Answers
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Rolling or sliding window iterator?
I need a rolling window (aka sliding window) iterable over a sequence/iterator/generator. Default Python iteration can be considered a special case, where the window length is 1. I'm currently using the following code. Does anyone have a more Pythonic, less verbose, or more efficient method for d...
Ruby on Rails generates model field:type - what are the options for field:type?
I'm trying to generate a new model and forget the syntax for referencing another model's ID. I'd look it up myself, but I haven't figured out, among all my Ruby on Rails documentation links, how to find the definitive source.
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std::vector versus std::array in C++
What are the difference between a std::vector and an std::array in C++? When should one be preferred over another? What are the pros and cons of each? All my textbook does is list how they are the same.
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Iterate two Lists or Arrays with one ForEach statement in C#
This just for general knowledge:
11 Answers
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Benefit of using Parcelable instead of serializing object
As I understand, Bundle and Parcelable belongs to the way Android performs serialization in. It is used for example in passing data between activities. But I wonder, if there are any benefits in using Parcelable instead of classic serialization in case of saving state of my business objects to...
Mockito matcher and array of primitives
With Mockito, I want to verify() a method call with byte[] in its argument list, but I didn't find how to write this.
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Stopping python using ctrl+c
I have a python script that uses threads and makes lots of HTTP requests. I think what's happening is that while a HTTP request (using urllib2) is reading, it's blocking and not responding to Ctrl C to stop the program. Is there any way around this?
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How to calculate a time difference in C++
What's the best way to calculate a time difference in C++? I'm timing the execution speed of a program, so I'm interested in milliseconds. Better yet, seconds.milliseconds..
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