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PostgreSQL: insert from another table
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Just supply literal values in the SELECT:
INSERT INTO TABLE1 (id, col_1, col_2, col_3)
SELECT id, 'data1', 'data2', 'data3'
FROM TABLE2
WHERE col_a = 'something';
A select list can contain any value expression:
But the expressions in the select list do not have to reference any columns i...
@ variables in Ruby on Rails
...cope (current block)
@title is an instance variable - and is available to all methods within the class.
You can read more here:
http://strugglingwithruby.blogspot.dk/2010/03/variables.html
In Ruby on Rails - declaring your variables in your controller as instance variables (@title) makes them ava...
Scatterplot with too many points
...;- data.frame(x = rnorm(5000),y=rnorm(5000))
ggplot(df,aes(x=x,y=y)) + geom_point(alpha = 0.3)
Another convenient way to deal with this is (and probably more appropriate for the number of points you have) is hexagonal binning:
ggplot(df,aes(x=x,y=y)) + stat_binhex()
And there is also regula...
How to query nested objects?
...iness logic, then run a single query at the end: find(conditions, fields, callback);
– Ryan Wheale
May 21 '14 at 2:17
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Setup a Git server with msysgit on Windows [closed]
.../web/20100207010332/http://www.timdavis.com.au/…
– alldayremix
Dec 1 '12 at 5:01
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Semicolons superfluous at the end of a line in shell scripts?
...e superfluous, since the newline is also a command separator. case specifically needs double semicolons at the end of the last command in each pattern block; see help case for details.
share
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impro...
Passing arguments forward to another javascript function
...manipulate that before passing it along, for example: var copy = [].slice.call(arguments); <remove what you want> myFunc.apply(this, copy);
– Nick Craver♦
Feb 17 '12 at 11:18
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Installing libv8 gem on OS X 10.9+
...se the --with-system-v8 option.
Using RubyGems:
gem install libv8 [-v YOUR_VERSION] -- --with-system-v8
Using Bundler (in your Gemfile):
bundle config build.libv8 --with-system-v8
Please note that if you intend to run your own V8, you must install both V8 and its headers (found in libv8-dev for ...
Please explain the exec() function and its family
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Simplistically, in UNIX, you have the concept of processes and programs. A process is an environment in which a program executes.
The simple idea behind the UNIX "execution model" is that there are two operations you can do.
The first ...
Control cannot fall through from one case label
...is present. I have the following code. But I am getting a "Control cannot fall through from one case label" error.
8 Answer...