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how to generate migration to make references polymorphic
...
As far as I know, there's no built-in generator for polymorphic associations. Generate a blank migration and then modify it by hand according to your needs.
Update:
You'll need to specify which table you're changing. According to this S...
When should I use a NoSQL database instead of a relational database? Is it okay to use both on the s
... I use MySQL (or SQLite for testing).
If you need a NoSQL db you usually know about it, possible reasons are:
client wants 99.999% availability on
a high traffic site.
your data makes
no sense in SQL, you find yourself
doing multiple JOIN queries for
accessing some piece of information.
you are b...
What is digest authentication?
...yea, that's very simplified)
The server takes username and realm (plus it knows the URI the client is requesting) and it looks up the password for that username. Then it goes and does its own version of generate_md5_key(nonce, username, realm, URI, password_I_have_for_this_user_in_my_db)
It compares...
Difference between \n and \r?
...ng time. With the release of Mac OS X in 2001 (which is Unix-based), \n is now used.
– jbbuckley
Jul 25 '15 at 1:21
4
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“On-line” (iterator) algorithms for estimating statistical median, mode, skewness, kurtosis?
...r-moment statistics.
Median
Median is tough without sorted data. If you know, how many data points you have, in theory you only have to partially sort, e.g. by using a selection algorithm. However, that doesn't help too much with billions of values. I would suggest using frequency counts, see the ...
How to override the copy/deepcopy operations for a Python object?
...se where pickling and copying need to be different. In fact, I don't even know why copy tries to use the pickling protocol by default. Copying is for in-memory manipulation, pickling is for cross-epoch persistence; they are completely different things that bear little relation to each other.
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What is meant by Scala's path-dependent types?
... upon the values passed to the constructor, not the b1/b2. I understand it now, but it took me a few reads to get it.
– Matthew Farwell
Sep 30 '11 at 14:50
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How to write to a JSON file in the correct format
...mp.json","w") do |f|
f.write(tempHash.to_json)
end
Your temp.json file now looks like:
{"key_a":"val_a","key_b":"val_b"}
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How do I make a reference to a figure in markdown using pandoc?
.... an extension to pandoc markdown syntax to allow identifiers for pictures now finally is under way. stay tuned :)
– Susanne Oberhauser
Dec 8 '14 at 15:37
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SQL Server: Filter output of sp_who2
... sp
JOIN master.dbo.sysdatabases sd ON sp.dbid = sd.dbid
ORDER BY spid
Now you can easily add any ORDER BY or WHERE clauses you like to get meaningful output.
Alternatively, you might consider using Activity Monitor in SSMS (Ctrl + Alt + A) as well
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