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Show constraints on tables command
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Beware that MariaDB starting with 10.2 will return awkward results here. jira.mariadb.org/browse/MDEV-15377
– stamster
Feb 24 '18 at 18:14
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try {} without catch {} possible in JavaScript?
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It's possible to have an empty catch block, without an error variable, starting with ES2019. This is called optional catch binding and was implemented in V8 v6.6, released in June 2018. The feature has been available since Node 10, Chrome 66, Firefox 58, Opera 53 and Safari 11.1.
The syntax is ...
Set environment variables from file of key/value pairs
...e tested this with bash 3.2.51(1)-release
Update:
To ignore lines that start with #, use this (thanks to Pete's comment):
export $(grep -v '^#' .env | xargs)
And if you want to unset all of the variables defined in the file, use this:
unset $(grep -v '^#' .env | sed -E 's/(.*)=.*/\1/' | xarg...
Paste multiple columns together
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# your starting data..
data <- data.frame('a' = 1:3, 'b' = c('a','b','c'), 'c' = c('d', 'e', 'f'), 'd' = c('g', 'h', 'i'))
# columns to paste together
cols <- c( 'b' , 'c' , 'd' )
# create a new column `x` with the three co...
Loader lock error
...came this error by creating the object-instance in an extra thread:
ThreadStart threadRef = new ThreadStart(delegate { m_ComObject = Activator.CreateInstance(Type.GetTypeFromProgID("Fancy.McDancy")); });
Thread myThread = new Thread(threadRef);
myThread.Start();
myThread.Join(); // for synchroniza...
How to change the default encoding to UTF-8 for Apache?
... by @Robbert earlier - if you are not already using .htaccess files, don't start now. There are performance & administrative reasons why this is a Bad Idea(tm)
– Signal15
Dec 10 '14 at 21:11
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Automatically open Chrome developer tools when new tab/new window is opened
...I was not able to find an option to keep Developer Tools always enabled on startup.
13 Answers
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PHP Array to CSV
...pen('php://memory','w');
$header=array("asdf ","asdf","asd","Calasdflee","Start Time","End Time" );
fputcsv($f,$header);
fputcsv($f,$header);
fputcsv($f,$header);
fseek($f,0);
header('content-type:text/csv');
header('Content-Disposition: attachment; filename="' . $filename . '";');
f...
How to exit an if clause
...l and sundry that function calls were really, really cheap in C. Everybody started writing small functions and modularizing. Years later we found out that function calls were still expensive on the PDP-11, and VAX code was often spending 50% of its time in the CALLS instruction. Dennis had lied to u...
How does the NSAutoreleasePool autorelease pool work?
..._init init];
}
That does not consume any more memory than it you already started with (assuming init doesn't instantiate objects, but you're not responsible for those anyway).
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