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What do REFRESH and MERGE mean in terms of databases?
...adable):
MERGE - for existing objects, to merge the existing data in the table with the data in my object. (sync to database)
PERSIST - is create new records from object in the database.
REFRESH - is to refresh the data in the object. Perhaps there was a change on the database which needs to be sy...
django models selecting single field
I have a table/models called Employees and I would like to get all rows of a single field as a queryset.
5 Answers
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Is there a job scheduler library for node.js? [closed]
...ter termination of nodejs process, all jobs will be lost. There is no cron table shipped with node-cron
– Upvote
Apr 24 '14 at 10:06
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Ways to eliminate switch in code [closed]
...attern, whether implemented with a switch statement, if else chain, lookup table, oop polymorphism, pattern matching or something else.
Do you want to eliminate the use of the "switch statement" or the "switch pattern"? The first one can be eliminated, the second one, only if another pattern/algori...
Understanding __get__ and __set__ and Python descriptors
...th the Temperature class). For example:
temp=Temperature()
temp.celsius #calls celsius.__get__
Accessing the property you assigned the descriptor to (celsius in the above example) calls the appropriate descriptor method.
instance in __get__ is the instance of the class (so above, __get__ would r...
What do I use for a max-heap implementation in Python?
... amazed that there IS such a built-in solution in heapq. But then it is totally unreasonable that it is NOT even slightly mentioned at all in the official document! WTF!
– RayLuo
Apr 21 '15 at 6:48
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How to drop a PostgreSQL database if there are active connections to it?
...ns after they've finished with their current transaction and then drop the table(s) in question?
– paulkon
Apr 25 '15 at 17:07
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Using python's eval() vs. ast.literal_eval()?
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datamap = eval(raw_input('Provide some data here: ')) means that you actually evaluate the code before you deem it to be unsafe or not. It evaluates the code as soon as the function is called. See also the dangers of eval.
ast.literal_eval raises an exception if the input isn't a valid Python dat...
How do I modify the URL without reloading the page?
...modify the URL in the address bar client-side. For instance, if you have a table of data with paging, sorting and filtering, and want those things to be Ajax powered, but still update the URL so that the current state of the page is bookmarkable. I can understand the security risks with modifying t...
Relative imports in Python 2.7
... not determine what package Python thinks it is in. That depends, additionally, on how you load the file into Python (by running or by importing).
There are two ways to load a Python file: as the top-level script, or as a
module. A file is loaded as the top-level script if you execute it directl...