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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)?
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Why am I seeing an “origin is not allowed by Access-Control-Allow-Origin” error here? [duplicate]
...quests outside of the current domain.
Ex 1: your domain is example.com and you want to make a request to test.com => you cannot.
Ex 2: your domain is example.com and you want to make a request to inner.example.com => you cannot.
Ex 3: your domain is example.com:80 and you want to make a...
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):
...
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...
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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How to list all Git tags?
In my repository, I have created tags using the following commands.
10 Answers
10
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