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Update multiple rows in same query using PostgreSQL
... one column, it's much more generalizable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c...
Can I create links with 'target=“_blank”' in Markdown?
...d, you'll just have to use HTML.
<a href="http://example.com/" target="_blank">Hello, world!</a>
Most Markdown engines I've seen allow plain old HTML, just for situations like this where a generic text markup system just won't cut it. (The StackOverflow engine, for example.) They then...
Rails I18n validation deprecation warning
... the following line inside the Rails::Application body
config.i18n.enforce_available_locales = true
The possible values are:
false: if you
want to skip the locale validation
don't care about locales
true: if you
want the application to raise an error if an invalid locale is passed (or)
wan...
pydot and graphviz error: Couldn't import dot_parser, loading of dot files will not be possible
...workX (e.g. this NetworkX example failed). I kept getting: global name 'dot_parser' is not defined. Your solution solved this problem.
– qtips
Aug 6 '13 at 0:41
...
How to implement a rule engine?
...;
// use a method call, e.g. 'Contains' -> 'u.Tags.Contains(some_tag)'
return Expression.Call(left, method, right);
}
}
Note that I used 'GreaterThan' instead of 'greater_than' etc. - this is because 'GreaterThan' is the .NET name for the operator, therefore we don't need any...
What is the difference between require_relative and require in Ruby?
What is the difference between require_relative and require in Ruby?
7 Answers
7
...
How can I check for Python version in a program that uses new language features?
...oesn't have ternary
Also, with is available in Python 2.5, just add from __future__ import with_statement.
EDIT: to get control early enough, you could split it into different .py files and check compatibility in the main file before importing (e.g. in __init__.py in a package):
# __init__.py
#...
MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback.
...
Test if a variable is a list or tuple
...
How about: hasattr(a, "__iter__") ?
It tells if the object returned can be iterated over as a generator. By default, tuples and lists can, but not the string types.
share...
iOS 7 status bar back to iOS 6 default style in iPhone app?
...Options, call
if (NSFoundationVersionNumber > NSFoundationVersionNumber_iOS_6_1) {
[application setStatusBarStyle:UIStatusBarStyleLightContent];
self.window.clipsToBounds =YES;
self.window.frame = CGRectMake(0,20,self.window.frame.size.width,self.window.frame.size.height-20);
/...