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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...
What is the purpose of a self executing function in javascript?
...
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
...
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
...
What is an MvcHtmlString and when should I use it?
...T 4 introduces a new code nugget syntax <%: %>. Essentially, <%: foo %> translates to <%= HttpUtility.HtmlEncode(foo) %>. The team is trying to get developers to use <%: %> instead of <%= %> wherever possible to prevent XSS.
However, this introduces the problem that ...
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...
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?
...
How do .gitignore exclusion rules actually work?
...so git won't look inside) instead of the files within the directory (which allows for the exclusion).
Think of the exclusions as saying "but not this one" rather than "but include this" - "ignore this directory (/a/b/c/) but not this one (foo)" doesn't make much sense; "ignore all files in this dir...
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
...
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...
Display filename before matching line
... If grep is supplied with multiple file names, it will automatically display the file names before the match, but it will leave the file name out in case of a single input file. By using /dev/null as an extra input file grep "thinks" it dealing with multiple files, but /dev/null is of cou...