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Is there any difference between “!=” and “” in Oracle Sql?
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No there is no difference at all in functionality.
(The same is true for all other DBMS - most of them support both styles):
Here is the current SQL reference: https://docs.oracle.com/database/121/SQLRF/conditions002.htm#CJAGAABC
The SQL standard only...
Calling virtual functions inside constructors
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Calling virtual functions from a constructor or destructor is dangerous and should be avoided whenever possible. All C++ implementations should call the version of the function defined at the level of the hierarchy in the cur...
How do I execute a bash script in Terminal?
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The advice to cd anywhere at all perpetrates another common beginner misunderstanding. Unless the script internally has dependencies which require it to run in a particular directory (like, needing to read a data file which the script inexplicably doesn'...
what is reverse() in Django
...!-- django <= 1.4 -->
<a href="{% url url_name %}">link which calls some_view</a>
<!-- django >= 1.5 or with {% load url from future %} in your template -->
<a href="{% url 'url_name' %}">link which calls some_view</a>
This will be rendered as:
<a href="...
django : using select_related and get_object_or_404 together
Is there any way of using get_object_or_404 and select_related together or any other way to achieve the result of using these two together(except from putting it in try/except)??
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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
...he top answer is flawed in my opinion. Hopefully, no one is mass importing all of pandas into their namespace with from pandas import *. Also, the map method should be reserved for those times when passing it a dictionary or Series. It can take a function but this is what apply is used for.
So, if ...
When should Flask.g be used?
...st without change to code.
The application context is popped after teardown_request is called. (Armin's presentation explains this is because things like creating DB connections are tasks which setup the environment for the request, and should not be handled inside before_request and after_request)
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How can I obtain the element-wise logical NOT of a pandas Series?
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Wierd, I actually tested the tilde as it was mentioned in the documentation, but it didn't perform the same as np.invert :S
– root
Apr 14 '13 at 13:11
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Determine direct shared object dependencies of a Linux binary?
...information. If you invoke objdump with the -x option, to get it to output all headers then you'll find the shared object dependencies right at the start in the "Dynamic Section".
For example running objdump -x /usr/lib/libXpm.so.4 on my system gives the following information in the "Dynamic Sectio...
How to delete migration files in Rails 3
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I usually:
Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete.
Delete the migration file manually.
If there are pending migrations (i.e., the migration I removed was not the...