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Delete everything in a MongoDB database
...way everything in a database—that is, to delete every single collection, and whatever else might be lying around, and start from scratch. Is there a single line of code that will let me do this? Bonus points for giving both a MongoDB console method and a MongoDB Ruby driver method.
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What is the difference between active and passive FTP?
Can someone tell me what is the difference between active and passive FTP?
Which one is preferable?
5 Answers
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Should switch statements always contain a default clause?
...pe! based on the language,
// there should probably be some error-handling
// here, maybe an exception
}
2. To handle 'default' actions, where the cases are for special behavior.
You see this a LOT in menu-driven programs and bash shell scripts. You might also see this when a vari...
Importance of varchar length in MySQL table
...serted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessary?
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The differences between .build, .create, and .create! and when should they be used?
So I've been seeing people using .build , .create , and .create! within their controllers more and more lately. What's the difference from just using .new and passing the param'd object and then .save ? Are there pros and cons? Does using these other methods offer benefits?
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Hidden features of Ruby
...actually wrote an gem at one point to do this, but my code was (a) a mess, and (b) slow. I'm very glad that the functionality has made it into core.
– James A. Rosen
Dec 14 '09 at 13:47
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How to fetch the row count for all tables in a SQL SERVER database [duplicate]
... table_name varchar(255),
row_count int
)
EXEC sp_MSForEachTable @command1='INSERT #counts (table_name, row_count) SELECT ''?'', COUNT(*) FROM ?'
SELECT table_name, row_count FROM #counts ORDER BY table_name, row_count DESC
DROP TABLE #counts
The output will be a list of tables and their row ...
Iterating over every two elements in a list
...+ y)
In Python 3, you can replace izip with the built-in zip() function, and drop the import.
All credit to martineau for his answer to my question, I have found this to be very efficient as it only iterates once over the list and does not create any unnecessary lists in the process.
N.B: This ...
virtualenv --no-site-packages and pip still finding global packages?
...on that virtualenv --no-site-packages would create a completely separate and isolated Python environment, but it doesn't seem to.
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Find a pair of elements from an array whose sum equals a given number
Given array of n integers and given a number X, find all the unique pairs of elements (a,b), whose summation is equal to X.
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