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What is the purpose of a self executing function in javascript?
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It's all about variable scoping. Variables declared in the self executing function are, by default, only available to code within the self executing function. This allows code to be written without concern of how variables are nam...
Populating Spring @Value during Unit Test
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Or even without Spring dependencies at all by changing the field to default access (package protected) to make it simply accessible to the test.
– Arne Burmeister
Jan 13 '16 at 10:03
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Use of “global” keyword in Python
...l variables is seldom considered a good solution.
def bob():
me = "locally defined" # Defined only in local context
print(me)
bob()
print(me) # Asking for a global variable
The above will give you:
locally defined
Traceback (most recent call last):
File "file.py", line 9, in &l...
Re-raise exception with a different type and message, preserving existing information
...ns that it can raise (e.g. inheriting from a FooError abstract class for all the foo module's specific exceptions). This allows users of the module to catch those particular exceptions and handle them distinctly, if needed. But many of the exceptions raised from the module are raised because of ...
Turn off constraints temporarily (MS SQL)
I'm looking for a way to temporarily turn off all DB's constraints (eg table relationships).
5 Answers
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MySQL: How to copy rows, but change a few fields?
...r table has like 1000 columns or something and you don't want to type them all, then you could write a SQL statement to build your SQL statement :). The way you would do it would be to use the information_schema to get the column names for the table. But that's really overkill, I'd just type out the...
postgresql return 0 if returned value is null
...ns the first of its arguments that is not null.
Null is returned only if all arguments are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cum...
How do I create a file AND any folders, if the folders don't exist?
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You can blindly call Directory.CreateDirectory without the Directory.Exists check first - it won't throw if the directory is already there.
– Tim Robinson
Jul 8 '10 at 8:14
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mkdir -p functionality in Python [duplicate]
...hell from within Python. I am looking for a solution other than a system call. I am sure the code is less than 20 lines, and I am wondering if someone has already written it?
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Best practices for in-app database migration for Sqlite
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I maintain an application that periodically needs to update a sqlite database and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing w...