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ALTER TABLE without locking the table?
...n doing an ALTER TABLE statement in MySQL, the whole table is read-locked (allowing concurrent reads, but prohibiting concurrent writes) for the duration of the statement. If it's a big table, INSERT or UPDATE statements could be blocked for a looooong time. Is there a way to do a "hot alter", like ...
LaTeX table positioning
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This is a really really useful package. Thanks for sharing!
– John David
Jun 9 at 3:30
add a comment
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“Least Astonishment” and the Mutable Default Argument
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Actually, this is not a design flaw, and it is not because of internals, or performance.
It comes simply from the fact that functions in Python are first-class objects, and not only a piece of code.
As soon as you get to think i...
Align DIV's to bottom or baseline
... I doubt this does what he wants, currently this will position all (looks as though there will be multiple child elements if its a dynamic bar chart) on top of each other.
– crmepham
Dec 14 '13 at 6:55
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Difference between initLoader and restartLoader in LoaderManager
...f the abstract LoaderManager, is much more enlightening.
initLoader
Call to initialize a particular ID with a Loader. If this ID already
has a Loader associated with it, it is left unchanged and any previous
callbacks replaced with the newly provided ones. If there is not
currently a L...
Windows: How to specify multiline command on command prompt?
...sort of dangerous answer for you.
Trying to use this with things that actually use piping, like say findstr is quite problematic. The same goes for dealing with elses. But if you just want a multi-line conditional command to execute directly from CMD and not via a batch file, this should do work we...
How to construct a timedelta object from a simple string
...on, without having to resort to external libraries such as dateutil or manually parsing the input, is to use datetime's powerful strptime string parsing method.
from datetime import datetime, timedelta
# we specify the input and the format...
t = datetime.strptime("05:20:25","%H:%M:%S")
# ...and us...
Removing a model in rails (reverse of “rails g model Title…”)
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It removes all, but it do not create downgrade migration or something.
– mr.The
Feb 12 '14 at 18:10
add a comme...
Difference between viewDidLoad and viewDidAppear
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viewDidLoad is called exactly once, when the view controller is first loaded into memory. This is where you want to instantiate any instance variables and build any views that live for the entire lifecycle of this view controller. However, t...
Why does C++ require a user-provided default constructor to default-construct a const object?
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This was considered a defect (against all versions of the standard) and it was resolved by Core Working Group (CWG) Defect 253. The new wording for the standard states in http://eel.is/c++draft/dcl.init#7
A class type T is const-default-constructible if
def...