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What is a columnar database?
... simply storing the info in tables with one (or rather often two) columns (and adding the necessary layer to access the columnar data in an easy fashion).
How do they differ from relational databases?
They generally differ from traditional (row-oriented) databases with regards to ...
performance....
How can I delete the current line in Emacs?
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If you want to delete a number of whole lines, you can prefix the command with a number:
C-u 5 C-S-backspace # deletes 5 whole lines
M-5 C-S-backspace # deletes 5 whole lines
C-u C-S-backspace # delete 4 whole lines. C-u without a number defaults to 4
C-u -5 C-S-backspace # de...
Convert a String representation of a Dictionary to a dictionary?
... literal structures: strings, numbers, tuples, lists, dicts, booleans,
and None.
For example:
>>> eval("shutil.rmtree('mongo')")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "<string>", line 1, in <module>
File "/opt/Python...
How to grab substring before a specified character jQuery or JavaScript
...fore the ',' comma. How do I do this in JavaScript or jQuery? I tried this and not working..
11 Answers
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parseInt vs unary plus, when to use which?
...ore like parseFloat since it also accepts decimals.
parseInt on the other hand stops parsing when it sees a non-numerical character, like the period that is intended to be a decimal point ..
+'2.3' === 2.3; //true
parseInt('2.3',10) === 2; //true
parseInt and parseFloat parses and bu...
When monkey patching an instance method, can you call the overridden method from the new implementat
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EDIT: It has been 9 years since I originally wrote this answer, and it deserves some cosmetic surgery to keep it current.
You can see the last version before the edit here.
You can’t call the overwritten method by name or keyword. That’s one of the many reasons why monkey patching...
PHP date() format when inserting into datetime in MySQL
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The problem is that you're using 'M' and 'D', which are a textual representations, MySQL is expecting a numeric representation of the format 2010-02-06 19:30:13
Try: date('Y-m-d H:i:s') which uses the numeric equivalents.
edit: switched G to H, though it may not...
Is there a Unix utility to prepend timestamps to stdin?
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Could try using awk:
<command> | awk '{ print strftime("%Y-%m-%d %H:%M:%S"), $0; fflush(); }'
You may need to make sure that <command> produces line buffered output, i.e. it flushes its output stream after each line; the timestamp awk adds ...
Contains case insensitive
... The latter method is more correct; the former will fail for the Turkish I and any other such problematic uppercase/lowercase pairs: i18nguy.com/unicode/turkish-i18n.html
– Domenic
Jan 24 '12 at 20:44
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Visual Studio - Shortcut to Navigate to Solution Explorer
Is there a keyboard shortcut in Visual Studio (aside from CTRL + TAB and selection) that would take me from inside a document directly into the solution explorer? I don't want to customize any shortcuts or change any default behavior.
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