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Insert auto increment primary key to existing table
...ering if it's possible to insert data into the primary key column automatically (I already have 500 rows in DB and want to give them id but I don't want to do it manually). Any thoughts? Thanks a lot.
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Why does ++[[]][+[]]+[+[]] return the string “10”?
...array ([]). Due to references it's wrong to say [[]][0] === [], but let's call the inner array A to avoid the wrong notation.
++ before its operand means “increment by one and return the incremented result”. So ++[[]][0] is equivalent to Number(A) + 1 (or +A + 1).
Again, we can simplify the me...
Two-way encryption: I need to store passwords that can be retrieved
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Personally, I would use mcrypt like others posted. But there is much more to note...
How do I encrypt and decrypt a password in PHP?
See below for a strong class that takes care of everything for you:
What is the safest algorit...
Rename specific column(s) in pandas
I've got a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answe...
UITextView style is being reset after setting text property
I have UITextView *_masterText and after call method setText property font is being reset.
It's happening after I change sdk 7.
_masterText is IBOutlet , global and properties are set in storyboard. It's only me or this is general SDK bug?
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What does the “at” (@) symbol do in Python?
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Example
class Pizza(object):
def __init__(self):
self.toppings = []
def __call__(self, topping):
# When using '@instance_of_pizza' before a function definition
# the function gets passed onto 'topping'.
self.toppings.appe...
Pandas percentage of total with groupby
... is a table of some kind, so 100 * x doesn't intuitively make sense (especially when some of the cells contain strings like AZ, ...).
– dhardy
Feb 6 '15 at 9:42
6
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Export and Import all MySQL databases at one time
I want to keep a backup of all my MySQL databases. I have more than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
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What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
... platforms, memory leaks are often caused by unreleased pointers. Traditionally, it has always been of utmost importance to check your allocs, copies and retains to make sure each has a corresponding release message.
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Convert a python 'type' object to a string
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print type(someObject).__name__
If that doesn't suit you, use this:
print some_instance.__class__.__name__
Example:
class A:
pass
print type(A())
# prints <type 'instance'>
print A().__class__.__name__
# prints A
Also, it seems th...