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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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Getting key with maximum value in dictionary?
...b':3000, 'c': 100}
max(stats.iteritems(), key=operator.itemgetter(1))[0]
And instead of building a new list in memory use stats.iteritems(). The key parameter to the max() function is a function that computes a key that is used to determine how to rank items.
Please note that if you were to have ...
Error: allowDefinition='MachineToApplication' beyond application level
...he most recent build I had was Debug. I opened the solution, did a bug fix and attempted to build in RRelease mode. Cleaning in Release didn't work but cleaning in Debug did. (Probably a combo of the 2 was what was needed, i.e. clear out any old refs to dlls, whether Debug or Release).
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Uploading both data and files in one form using Ajax?
I'm using jQuery and Ajax for my forms to submit data and files but I'm not sure how to send both data and files in one form?
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