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When NOT to use Cassandra?
...to solve specific problems and has its own pros and cons. It is up to you, what problem statement you have and what is the best fitting solution for that problem.
I will try to answer your questions one by one in the same order you asked them. Since Cassandra is based on the NoSQL family of databas...
SQL query to group by day
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actually this depends on what DBMS you are using but in regular SQL convert(varchar,DateColumn,101) will change the DATETIME format to date (one day)
so:
SELECT
sum(amount)
FROM
sales
GROUP BY
convert(varchar,created,101)
the mag...
How do I make HttpURLConnection use a proxy?
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What if you have different username/password pairs for the different proxies? Calling a static method to set the default Authenticator isn't ideal, this is not much better than setting the sys properties method..
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How to select only the first rows for each unique value of a column
... question. You'd use the 2nd technique or Ben Thul's technique. I answered what you asked specifically, with pointers on how to solve more generally.
– gbn
Jan 12 '11 at 4:53
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Linux find file names with given string
...ought I'd throw in something helpful in a different way; if you can sum up what you're trying to achieve in one word, there's a mighty fine help feature on Linux.
man -k <your search term>
What that does is to list all commands that have your search term in the short description. There's u...
How to add “on delete cascade” constraints?
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Thanks, that is what I thought too - but what to do with FOREIGN KEYs? Are they just constraints (similar to NOT NULL) which can be dropped and readded easily?
– Alexander Farber
Apr 27 '12 at 19:37
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Failed to allocate memory: 8
...eed to specify AVD resolution forcefully : 800 x 1280. It starts my AVD as what I required
– Nirav Shah
Sep 28 '12 at 9:14
4
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Number of processors/cores in command line
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nproc is what you are looking for.
More here : http://www.cyberciti.biz/faq/linux-get-number-of-cpus-core-command/
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Why can't I define a default constructor for a struct in .NET?
...eters. According to this post this is mandated by the CLI specification. What happens is that for every value-type a default constructor is created (by the compiler?) which initialized all members to zero (or null ).
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How do you force a CIFS connection to unmount
...symlink pointing inside the CIFS mount and ls tries to follow it to decide what color it should be. If I try to umount it (even with -fl), the umount process hangs just like ls does. Not even sudo kill -9 can kill it. How can I force the kernel to unmount?
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