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Capturing Groups From a Grep RegEx
..._[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
echo "$f doesn't...
How to 'insert if not exists' in MySQL?
I started by googling, and found this article which talks about mutex tables.
10 Answers
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How to select rows that have current day's timestamp?
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use DATE and CURDATE()
SELECT * FROM `table` WHERE DATE(`timestamp`) = CURDATE()
I guess using DATE still uses INDEX.
see the execution plan on the DEMO
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Find the host name and port using PSQL commands
I have PSQL running, and am trying to get a perl application connecting to the database. Is there a command to find the current port and host that the database is running on?
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What does the “at” (@) symbol do in Python?
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An @ symbol at the beginning of a line is used for class, function and method decorators.
Read more here:
PEP 318: Decorators
Python Decorators
The most common Python decorators you'll run into are:
@property
@classmethod
@staticmethod
If you see an @ in the middle of a line, that's ...
[ :Unexpected operator in shell programming [duplicate]
...et of sh syntax - the /bin/sh executable on your system may provide only standard sh functionality, in which []-style tests are not included.
– Tim
Aug 5 '10 at 1:17
13
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Pass a data.frame column name to a function
I'm trying to write a function to accept a data.frame ( x ) and a column from it. The function performs some calculations on x and later returns another data.frame. I'm stuck on the best-practices method to pass the column name to the function.
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Resize HTML5 canvas to fit window
...get rid of the scrollbars, add "overflow: hidden" to the style of the html and body elements. See thefutureoftheweb.com/blog/100-percent-height-interface
– Denis Washington
Mar 16 '12 at 7:45
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Conversion of a datetime2 data type to a datetime data type results out-of-range value
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I changed my datacolumns and used typeof now... Further I found my problem. there was 1 datarow that contained a wrong date, which triggered the error
– Gerbrand
Aug 26 '09 at 5:46
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Extending from two classes
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You can only Extend a single class. And implement Interfaces from many sources.
Extending multiple classes is not available. The only solution I can think of is not inheriting either class but instead having an internal variable of each class and doing more o...