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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'...
How do I execute a string containing Python code in Python?
...;>> x
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However, the first step should be to ask yourself if you really need to. Executing code should generally be the position of last resort: It's slow, ugly and dangerous if it can contain user-entered code. You should always look at alternatives first, such as higher order functions, ...
Why would a JavaScript variable start with a dollar sign? [duplicate]
...wish the jquery documentation used this notation as well... It is indeed really helpful.
– pedromanoel
Jan 28 '14 at 11:05
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Is Python strongly typed?
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Python is strongly, dynamically typed.
Strong typing means that the type of a value doesn't change in unexpected ways. A string containing only digits doesn't magically become a number, as may happen in Perl. Every change of type requires an explicit...
Delete multiple objects in django
...sing a webpage. There is no category to select from so I can't delete from all of them like that. Do I have to implement my own delete form and process it in django or does django have a way to already do this? As its implemented in the admin interface.
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Fast Linux File Count for a large number of files
...ke a while if there are a lot of them. Also there will be no output until all of the names are read and sorted. Use the ls -f option to turn off sorting.
ls -f | wc -l
Note that this will also enable -a, so ., .., and other files starting with . will be counted.
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PowerShell equivalent to grep -f
...h/2011/03/powershell-search-for-string-or-grep-for-powershell/
But essentially it is:
Select-String -Path "C:\file\Path\*.txt" -Pattern "^Enter REGEX Here$"
This gives a directory file search (*or you can just specify a file) and a file-content search all in one line of PowerShell, very similar ...
Is Java “pass-by-reference” or “pass-by-value”?
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Java is always pass-by-value.
Unfortunately, we never handle an object at all, instead juggling object-handles called references (which are passed by value of course). The chosen terminology and semantics easily confuse many beginners.
It goes like this:
public static void main(String[] args) {
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How do I include a file over 2 directories back?
.... And (2) you’d still use a relative path in your define, Unless you actually hard-code the whole absolute server path and I would refrain from that since it has only disadvantages. Or (the third alternative) you could use string manipulation to extract parent directory from the (expanded) current...
Add Variables to Tuple
... I think its important to note that tuples are immutable - they cannot actually be modified. What this solution does is create a new tuple based on two existing tuples.
– That1Guy
Jan 16 '19 at 20:58
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