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Rails: around_* callbacks
...api.rubyonrails.org/classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
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ORA-30926: unable to get a stable set of rows in the source tables
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This is usually caused by duplicates in the query specified in USING clause. This probably means that TABLE_A is a parent table and the same ROWID is returned several times.
You could quickly solve the problem by using a DISTINCT in yo...
How to access app.config in a blueprint?
...ation)
the_blueprint = RegisteringExampleBlueprint('example', __name__)
And an example using the record decorator:
from flask import Blueprint
from api import api_blueprint as api
auth = None
# Note there's also a record_once decorator
@api.record
def record_auth(setup_state):
global auth
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Google Espresso or Robotium [closed]
..., but also cause tests to run slower than necessary.
API. Espresso has a small, well-defined and predictable API, which is open to customization. You tell the framework how to locate a UI element using standard hamcrest matchers and then instruct it to either perform an action or check an assertion ...
Calculate distance between two points in google maps V3
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@EmanuelePaolini - Mathematically, atan2(sqrt(a),sqrt(1-a)) = asin(sqrt(a)) = acos(sqrt(1-a)), but the atan2 version remains numerically better conditioned for all values of a.
– ChrisV
Dec 19 '14 at 18:00
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What is the best way to repeatedly execute a function every x seconds?
...er (just like an NSTimer in Objective C). This code will run as a daemon and is effectively like calling the python script every minute using a cron, but without requiring that to be set up by the user.
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Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
What is a stored procedure?
... a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples.
To create a stored procedure the syntax is fairly simple:
CRE...
powershell 2.0 try catch how to access the exception
...tch [Net.WebException] {
$_ | fl * -Force
}
I think it will give you all the info you need.
My rule: if there is some data that is not displayed, try to use -force.
share
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improve this answe...
Should I use the datetime or timestamp data type in MySQL?
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Timestamps in MySQL are generally used to track changes to records, and are often updated every time the record is changed. If you want to store a specific value you should use a datetime field.
If you meant that you want to decide between using a UNIX ...