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How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...TER TABLE test1 ADD COLUMN id INTEGER;
CREATE SEQUENCE test_id_seq OWNED BY test1.id;
ALTER TABLE test ALTER COLUMN id SET DEFAULT nextval('test_id_seq');
UPDATE test1 SET id = nextval('test_id_seq');
Again, in recent versions of Postgres this is roughly equivalent to the single command abov...
Best way to repeat a character in C#
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Make it better by doing it without Linq and with StruingBuilder!
– Bitterblue
Apr 15 '14 at 15:29
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MySql: Tinyint (2) vs tinyint(1) - what is the difference?
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@realtebo it's mainly used by the mysql command line client for display purposes.
– Ja͢ck
Oct 12 '12 at 23:25
3
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Using XPATH to search text containing
...s based on
how the text looks in the browser when
rendered. We do this by replacing all
non-visible whitespace (including the
non-breaking space " ") with a
single space. All visible newlines
(<br>, <p>, and <pre> formatted
new lines) should be preserved.
...
How can I push to my fork from a clone of the original repo?
...
By default, when you clone a repository
that resides at https://github.com/original/orirepo.git,
whose current branch is called master,
then
the local config of the resulting clone lists only one remote called origin, w...
Is Haxe worth learning? [closed]
... libraries for specific targets. Haxe tries to ease the pain of transition by having just one source language (the Haxe language) and many outputs (through the Haxe compiler). The language is very friendly and quite easy to learn, no matter your background.
Reading the website it looks very prom...
How do I compute derivative using Numpy?
...rences
Automatic Derivatives
Symbolic Differentiation
Compute derivatives by hand.
Finite differences require no external tools but are prone to numerical error and, if you're in a multivariate situation, can take a while.
Symbolic differentiation is ideal if your problem is simple enough. Symb...
Python division
...m __future__ import division you can get the old C-style division behavior by using two slashes (e.g. 1 // 2 will result in 0). See Pep 238 Changing the Division Operator
– User
Nov 28 '13 at 5:40
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Hiding the scroll bar on an HTML page
...tweaks.
Firefox 64 now supports the experimental scrollbar-width property by default (63 requires a configuration flag to be set). To hide the scrollbar in Firefox 64:
#element {
scrollbar-width: none;
}
To see if your current browser supports either the pseudo element or scrollbar-width, tr...
Is it possible to read from a InputStream with a timeout?
...ve found the opposite - it always returns the best value for the number of bytes available. Javadoc for InputStream.available():
Returns an estimate of the number of bytes that can be read (or skipped over)
from this input stream without blocking by the next invocation of a method for
this input...