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How can I have ruby logger log output to stdout as well as file?
...ime Logger calls puts on your MultiIO object, it will write to both STDOUT and your log file.
Edit: I went ahead and figured out the rest of the interface. A log device must respond to write and close (not puts). As long as MultiIO responds to those and proxies them to the real IO objects, this s...
How to declare a variable in MySQL?
... refer to a variable that has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BET...
1052: Column 'id' in field list is ambiguous
I have 2 tables. tbl_names and tbl_section which has both the id field in them. How do I go about selecting the id field, because I always get this error:
...
Python Process Pool non-daemonic?
...s creates the worker processes in its __init__ method, makes them daemonic and starts them, and it is not possible to re-set their daemon attribute to False before they are started (and afterwards it's not allowed anymore). But you can create your own sub-class of multiprocesing.pool.Pool (multiproc...
Are C++ enums signed or unsigned?
Are C++ enums signed or unsigned? And by extension is it safe to validate an input by checking that it is = your min value (assuming you started at 0 and incremented by 1)?
...
Access an arbitrary element in a dictionary in Python
...
On Python 3, non-destructively and iteratively:
next(iter(mydict.values()))
On Python 2, non-destructively and iteratively:
mydict.itervalues().next()
If you want it to work in both Python 2 and 3, you can use the six package:
six.next(six.itervalue...
Decorators with parameters?
...ecorator with arguments should return a function that will take a function and return another function. So it should really return a normal decorator. A bit confusing, right? What I mean is:
def decorator_factory(argument):
def decorator(function):
def wrapper(*args, **kwargs):
...
Python threading.timer - repeat function every 'n' seconds
I want to fire off a function every 0.5 seconds and be able to start and stop and reset the timer. I'm not too knowledgeable of how Python threads work and am having difficulties with the python timer.
...
What is database pooling?
I just wanted to know the concept of database connection pooling and how it is achieved.
6 Answers
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What is the meaning of the prefix N in T-SQL statements and when should I use it?
... This denotes that the subsequent string is in Unicode
(the N actually stands for National language character set). Which
means that you are passing an NCHAR, NVARCHAR or NTEXT value, as
opposed to CHAR, VARCHAR or TEXT.
To quote from Microsoft:
Prefix Unicode character string constants ...