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Why is sed not recognizing \t as a tab?
...n". And that is what most of us expect when we use things like \t, \r, \n, etc. From: https://www.gnu.org/software/bash/manual/html_node/ANSI_002dC-Quoting.html#ANSI_002dC-Quoting
Words of the form $'string' are treated specially. The word expands
to string, with backslash-escaped characters r...
Reducing Django Memory Usage. Low hanging fruit?
...t of apache virtual hosts already in place, using SSL with apache already, etc. In this case, use mod_wsgi. If you are starting afresh, use spawning. NEVER use mod_python.
– nosklo
Jan 29 '09 at 10:23
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How to install psycopg2 with “pip” on Python?
...d the issue for me. the easiest way to edit the path is to run "sudo nano /etc/path" from your terminal.
– tbradley22
Jul 13 '14 at 5:38
2
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How do I check if a directory exists? “is_dir”, “file_exists” or both?
...ent, but it's not a dir
//do something with file - delete, rename, etc.
unlink('file'); //for example
mkdir('file', NEEDED_ACCESS_LEVEL);
}
} else { //no file exists with this name
mkdir('file', NEEDED_ACCESS_LEVEL);
}
...
JavaScript before leaving the page
...
this can be overwritten by any other plugin etc, mostly developer made mistake with selector, if you are doubted about overwritten, put your jquery code before close of </body> tag.
– Wasim A.
Aug 9 '14 at 6:37
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How do I write a for loop in bash
...and allow counting/sequences by using the double periods (you can use a..z etc.). However, the double period syntax is a new feature of bash 3.0; earlier versions will not support this.
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Get itunes link for app before submitting
... Store on your device, which is not the App Store. You're then redirected, etc. The http://... link seems to be directly hooked to the App Store app.
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Haskell offline documentation?
...d you'll find things options like doc-index-file, docdir, datadir, prefix, etc that allow you to configure where the documentation is stored.
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A python class that acts like dict
..., has a _dict__ which contains all the object attributes (methods, fields, etc). You do not want to mess around with this unless you want to write code that is modifying itself...
– Raik
Feb 8 '19 at 12:49
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How do I check if a column is empty or null in MySQL?
...= ' ' IS TRUE
'' = ' ' IS TRUE
' ' = ' ' IS TRUE
' ' = ' ' IS TRUE
etc
Therefore, this should work regardless of how many spaces make up the some_col value:
SELECT *
FROM T
WHERE some_col IS NULL
OR some_col = ' ';
or more succinctly:
SELECT *
FROM T
WHERE NULLIF(some_c...