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Postgres DB Size Command
What is the command to find the size of all the databases?
10 Answers
10
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Grabbing the href attribute of an A element
...ml($node), PHP_EOL;
}
The above would find and output the "outerHTML" of all A elements in the $html string.
To get all the text values of the node, you do
echo $node->nodeValue;
To check if the href attribute exists you can do
echo $node->hasAttribute( 'href' );
To get the href att...
What is memory fragmentation?
...emory fragmentation" used a few times in the context of C++ dynamic memory allocation. I've found some questions about how to deal with memory fragmentation, but can't find a direct question that deals with it itself. So:
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How do I fix the indentation of an entire file in Vi?
In Vim, what is the command to correct the indentation of all the lines?
16 Answers
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Rails find record with zero has_many records associated [duplicate]
...92465 - also answers your question about constructing the inverse and does all this with Arel
– novemberkilo
Sep 29 '13 at 16:06
5
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Using -performSelector: vs. just calling the method
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Basically performSelector allows you to dynamically determine which selector to call a selector on the given object. In other words the selector need not be determined before runtime.
Thus even though these are equivalent:
[a...
How do I see the commit differences between branches in git?
... branch-X and have added a couple more commits on top of it. I want to see all the differences between MASTER and the branch that I am on in terms of commits. I could just do a
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Remove blank lines with grep
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Try the following:
grep -v -e '^$' foo.txt
The -e option allows regex patterns for matching.
The single quotes around ^$ makes it work for Cshell. Other shells will be happy with either single or double quotes.
UPDATE: This works for me for a file with blank lines or "all white ...
Which is preferred: Nullable.HasValue or Nullable != null?
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The compiler replaces null comparisons with a call to HasValue, so there is no real difference. Just do whichever is more readable/makes more sense to you and your colleagues.
share
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How can I pipe stderr, and not stdout?
...1 >/dev/null | grep 'something'
For the details of I/O redirection in all its variety, see the chapter on Redirections in the Bash reference manual.
Note that the sequence of I/O redirections is interpreted left-to-right, but pipes are set up before the I/O redirections are interpreted. File ...