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Ruby on Rails: How do I add a not null constraint to an existing column using a migration?
In my Rails (3.2) app, I have a bunch of tables in my database but I forgot to add a few not null constraints. I've googled around but I can't find how to write a migration which adds not null to an existing column.
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What is the best way to count “find” results?
...ull lines :
$ time find -type f | wc -l
8
real 0m0.006s
user 0m0.003s
sys 0m0.000s
So my solution is faster =) (the important part is the real line)
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Resolving LNK4098: defaultlib 'MSVCRT' conflicts with
... own CRT version to get their job done. It is located in c:\windows\system32, you cannot reliably use it for your own programs, its CRT headers are not available anywhere. The CRT DLL used by your program has a different name (like msvcrt90.dll).
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iOS Simulator failed to install the application
I have created a Cordova 2.1.0 app, It ran fine for the first 2-3 times. But now when I am trying to run it through terminal it is giving me the following error.I didn't change anything.
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Focus Next Element In Tab Index
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edited Jul 12 '18 at 15:13
Radek
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answered Aug 2...
Right mime type for SVG images with fonts embedded
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answered Aug 13 '12 at 8:20
Erik DahlströmErik Dahlström
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NSNotificationCenter addObserver in Swift
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idrougge
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answered Jun 4 '14 at 23:12
ConnorConnor
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python requests file upload
...http://example.com', files=files).prepare().body.decode('ascii'))
--c226ce13d09842658ffbd31e0563c6bd
Content-Disposition: form-data; name="upload_file"; filename="file.txt"
--c226ce13d09842658ffbd31e0563c6bd--
Note the filename="file.txt" parameter.
You can use a tuple for the files mapping val...
Retrieving the last record in each group - MySQL
...erflow August data dump. I'll use that for benchmarking. There are 1,114,357 rows in the Posts table. This is running on MySQL 5.0.75 on my Macbook Pro 2.40GHz.
I'll write a query to find the most recent post for a given user ID (mine).
First using the technique shown by @Eric with the GROUP BY...
XSD: What is the difference between xs:integer and xs:int?
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