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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
...s inline help:
\h ALTER TABLE
Also documented in the postgres docs (an em>x m>cellent resource, plus easy to read, too).
ALTER TABLE tablename ADD CONSTRAINT constraintname UNIQUE (columns);
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Apply CSS Style to child elements
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This code "div.test th, td, caption {padding:40pm>x m> 100pm>x m> 40pm>x m> 50pm>x m>;}" applies a rule to all th elements which are contained by a div element with a class named test, in addition to all td elements and all caption elements.
It is not the same as "all td, th and caption elem...
How to programmatically display version/build number of target in iOS app?
...for major updates to 2.0, 3.0, for minor updates to 1.1, 1.2 and for bug fim>x m>es to 1.0.1, 1.0.2 . This number is oriented about releases and new features. It does not have to stop at 9, 1.11.23 is a reasonable version number.
The build number is mostly the internal number of builds that have been ma...
How to get rspec-2 to give the full trace associated with a test failure?
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Yes! this is em>x m>actly what I needed. stack trace to the actual error not the spec stack.
– DiegoSalazar
Jan 31 '13 at 17:16
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Script parameters in Bash
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./ocrscript.sh -from /home/kristoffer/test.png -to /home/kristoffer/test.tm>x m>t
You'll get:
$0 # ocrscript.sh
$1 # -from
$2 # /home/kristoffer/test.png
$3 # -to
$4 # /home/kristoffer/test.tm>x m>t
It might be easier to omit the -from and the -to, like:
ocrscript.sh /home/kristoffer/tes...
How to make Twitter Bootstrap tooltips have multiple lines?
I am currently using the below function to create tem>x m>t that will be displayed using Bootstrap’s tooltip plugin. How come multiline tooltips only work with <br> and not \n ? I prefer that there is not any HTML in my links’ title attributes.
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How do I retrieve the number of columns in a Pandas data frame?
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done. @PhilCooper perhaps you could em>x m>plain why df.shape is better? my guess is that it does not call a function but just reads the attribute from memory?
– mkln
Nov 30 '13 at 18:59
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`staticmethod` and `abc.abstractmethod`: Will it blend?
...wered Dec 17 '10 at 20:26
Rosh Om>x m>ymoronRosh Om>x m>ymoron
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Select random lines from a file
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I ran this on a 500M row file to em>x m>tract 1,000 rows and it took 13 min. The file had not been accessed in months, and is on an Amazon EC2 SSD Drive.
– T. Brian Jones
Mar 4 '16 at 18:26
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Pass parameter to fabric task
... parameter to a fabric task when calling "fab" from the command line? For em>x m>ample:
5 Answers
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