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MySQL: selecting rows where a column is null
... NULL is always false).
See Rule 3 https://en.wikipedia.org/wiki/Codd%27s_12_rules
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ngClass style with dash in key
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edited Jan 25 '16 at 5:16
answered Mar 23 '13 at 1:39
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List comprehension rebinds names even after scope of comprehension. Is this right?
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List comprehensions leak the loop control variable in Python 2 but not in Python 3. Here's Gu...
Rails where condition using NOT NIL
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The canonical way to do this with Rails 3:
Foo.includes(:bar).where("bars.id IS NOT NULL")
A...
How to update attributes without validation
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USE update_attribute instead of update_attributes
Updates a single attribute and saves the re...
Why is Visual Studio 2013 very slow?
I'm running Visual Studio 2013 Pro (RTM version) on my formatted PC (Windows 8.1 fresh install).
31 Answers
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What are the differences between Generics in C# and Java… and Templates in C++? [closed]
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How to print the full NumPy array, without truncation?
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Python strptime() and timezones?
...'t work with %Z, so the case is important. See the following example:
In [1]: from datetime import datetime
In [2]: start_time = datetime.strptime('2018-04-18-17-04-30-AEST','%Y-%m-%d-%H-%M-%S-%Z')
In [3]: print("TZ NAME: {tz}".format(tz=start_time.tzname()))
TZ NAME: None
In [4]: start_time = d...
Insert text with single quotes in PostgreSQL
...$
Which can be nested any number of levels:
$token2$Inner string: $token1$escape ' with ''$token1$ is nested$token2$
Pay attention if the $ character should have special meaning in your client software. You may have to escape it in addition. This is not the case with standard PostgreSQL clients...