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Convert string to symbol-able in ruby
Symbols are usually represented as such
7 Answers
7
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Find MongoDB records where array field is not empty
All of my records have a field called "pictures". This field is an array of strings.
11 Answers
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Best way to get application folder path
...eful for accessing files whose location is relative to the application install directory.
In an ASP.NET application, this will be the application root directory, not the bin subfolder - which is probably what you usually want. In a client application, it will be the directory containing the main ex...
Is Big O(logn) log base e?
...nary search tree type of data structures, I see the Big O notation is typically noted as O(logn). With a lowercase 'l' in log, does this imply log base e (n) as described by the natural logarithm? Sorry for the simple question but I've always had trouble distinguishing between the different impli...
ActiveRecord: size vs count
...l valid.
You'll adapt the function you use depending on your needs.
Basically:
if you already load all entries, say User.all, then you should use length to avoid another db query
if you haven't anything loaded, use count to make a count query on your db
if you don't want to bother with these con...
Create an index on a huge MySQL production table without table locking
...d or dropped. The CREATE INDEX or DROP INDEX statement only finishes after all transactions that are accessing the table are completed, so that the initial state of the index reflects the most recent contents of the table. Previously, modifying the table while an index is being created or dropped ty...
How do I access command line arguments in Python?
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Python tutorial explains it:
import sys
print(sys.argv)
More specifically, if you run python example.py one two three:
>>> import sys
>>> print(sys.argv)
['example.py', 'one', 'two', 'three']
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How can I capture the result of var_dump to a string?
... most likely have a negative effect on performance here. It also can get really messy if you need to look at multiple variables during the execution of a complex script.
– selfawaresoup
Dec 27 '09 at 16:45
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Determine function name from within that function (without using traceback)
... Combining @CamHart's approach with @Yuval's avoids "hidden" and potentially deprecated methods in @RoshOxymoron's answer as well as numerical indexing into the stack for @neuro/@AndreasJung's answer: print(inspect.currentframe().f_code.co_name)
– hobs
Mar 1...
What's the difference between TRUNCATE and DELETE in SQL
...nces highlighted below.
General Overview
If you want to quickly delete all of the rows from a table, and you're really sure that you want to do it, and you do not have foreign keys against the tables, then a TRUNCATE is probably going to be faster than a DELETE.
Various system-specific issues h...