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How to query MongoDB with “like”?
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Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what'...
Why does sudo change the PATH?
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Yeah, but it's totally counterintuitive. It probably fools the good guys more than the bad guys.
– Brian Armstrong
Jun 20 '09 at 2:24
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How to convert JSON string to array
...d keys). That's what the documentation says and that's what my PHP 5.2 installation returns. Are you using a function other than the official, built-in json_decode()? What does var_dump(json_decode($str, true)); return?
– RickN
Sep 22 '11 at 15:34
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When to use EntityManager.find() vs EntityManager.getReference() with JPA
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I usually use getReference method when i do not need to access database state (I mean getter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful featu...
How to initialize a vector in C++ [duplicate]
...p;arr[0]+N; }
And then you can do this without having to repeat the size all over:
int vv[] = { 12,43 };
std::vector<int> v(begin(vv), end(vv));
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Only read selected columns
...g","Sep","Oct","Nov","Dec"))
dat <- fread("data.txt", drop = c(8:13))
All result in:
> data
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
UPDATE: When you don't want fread to return a data.table, use the data.ta...
How do I remove all specific characters at the end of a string in PHP?
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using rtrim replaces all "." at the end, not just the last character
$string = "something here..";
echo preg_replace("/\.$/","",$string);
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Random number generation in C++11: how to generate, how does it work? [closed]
...ad about it (what is that engine , maths term like distribution , "where all integers produced are equally likely ").
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Delete all tags from a Git repository
I want to delete all the tags from a Git repository. How can I do that?
11 Answers
11
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How to abandon a hg merge?
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Ah that is a good detail to know... actually I'm going to delete my comment claiming leaving off -r . is the same
– Thymine
Mar 1 '16 at 15:56
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