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How do I modify a MySQL column to allow NULL?
...ion and config can be NOT NULL specifying NULL as suggested by @ConroyP is more correct.
– Matthew Buckett
Jan 26 '16 at 13:37
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When should one use a spinlock instead of mutex?
...and if the lock is held for a longer amount of time, this will waste a lot more CPU time and it would have been much better if the thread was sleeping instead.
The Solution
Using spinlocks on a single-core/single-CPU system makes usually no sense, since as long as the spinlock polling is blocking ...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
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PHP - how to best determine if the current invocation is from CLI or web server?
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More straightforward: return php_sapi_name() == 'cli';
– Savageman
Aug 9 '10 at 19:18
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Python: Using .format() on a Unicode-escaped string
I am using Python 2.6.5. My code requires the use of the "more than or equal to" sign. Here it goes:
3 Answers
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Event handling for iOS - how hitTest:withEvent: and pointInside:withEvent: are related?
... with following SDK versions, but I think sending hitTest:withEvent: makes more sense because it provides a higher-level control of whether an event belongs to a view or not; pointInside:withEvent: tells whether the event location is on the view or not, not whether the event belongs to the view. For...
How to force a view refresh without having it trigger automatically from an observable?
...ur observables, but it's bad practice and conceivably fire off a whole lot more updates than you anticipate (think computed dependency chains).
– Patrick M
Aug 7 '12 at 16:18
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Why does “pip install” inside Python raise a SyntaxError?
...pip/issues/7498 for reference.
UPDATE: Since pip version 10.x there is no more get_installed_distributions() or main method under import pip instead use import pip._internal as pip.
UPDATE ca. v.18 get_installed_distributions() has been removed. Instead you may use generator freeze like this:
fro...
How can I define a composite primary key in SQL?
...a table can have at most one primary key. A primary key consists of one or more columns (from that table). If a primary key consists of two or more columns it is called a composite primary key. It is defined as follows:
CREATE TABLE voting (
QuestionID NUMERIC,
MemberID NUMERIC,
PRIMARY KEY (...
Squash the first two commits in Git? [duplicate]
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