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How can I create a unique constraint on my column (SQL Server 2008 R2)?

...the "General" tab. Make sure you have the column you want to make unique selected in the "columns" box. Change the "Type" box to "Unique Key". Click "Close". You see a little asterisk in the file window, this means changes are not yet saved. Press Save or hit Ctrl+s. It should save, and your colu...
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Cutting the videos based on start and end time using ffmpeg

...this answer if you don't need to trim at an exact milisecond, thus it will select the closest keyframe available. That's why it's so fast, it selects the closest keyframes and takes the snippet out without the need of reencoding. However, if you do need a precise time, taking the nearest keyframe is...
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When to use Hadoop, HBase, Hive and Pig?

... Consider that you work with RDBMS and have to select what to use - full table scans, or index access - but only one of them. If you select full table scan - use hive. If index access - HBase. s...
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Fastest way to extract frames using ffmpeg?

...actly which frames to extract, eg 1, 200, 400, 600, 800, 1000, try using: select='eq(n\,1)+eq(n\,200)+eq(n\,400)+eq(n\,600)+eq(n\,800)+eq(n\,1000)' \ -vsync vfr -q:v 2 I'm using this with a pipe to Imagemagick's montage to get 10 frames preview from any videos. Obviously the frame numbers ...
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Eclipse debugger always blocks on ThreadPoolExecutor without any obvious exception, why?

...Debugging perspective Go to its properties Go to Filtering In "Restrict to Selected Location(s)", click "Add Class" Add java.util.concurrent.ThreadPoolExecutor Untick the checkbox, meaning these will be ignored share ...
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Facebook database design?

...O_INCREMENT=2 DEFAULT CHARSET=utf8; Friends of Friends Query: ( select friend_id from friends where user_id = 1 ) union ( select distinct ff.friend_id from friends f join friends ff on ff.user_id = f.friend_id where f.use...
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Context switches much slower in new linux kernels

... One of the roles of BIOS feature selection is to enable/disable devices. In some cases these selections are forced on the OS (e.g., on-motherboard USB, eSATA and NICs). In others the OS is expected to respect your wishes (e.g., EIST, C states, Hyperthreading...
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What is the difference/usage of homebrew, macports or other package installation tools? [closed]

...to do the same with Homebrew. MacPorts support groups. foo@macpro:~/ port select --summary Name Selected Options ==== ======== ======= db none db46 none gcc none gcc42 llvm-gcc42 mp-gcc48 none llvm none mp-llvm-3.3 none mys...
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How to calculate time in hours between two dates in iOS

...developer.apple.com/library/mac/navigation/ or if you are using Xcode just select help/documentation from the menu. See: how-to-convert-an-nstimeinterval-seconds-into-minutes --edit: See ÐąrέÐέvil's answer below for correctly handling daylight savings/leap seconds ...
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Can the :not() pseudo-class have multiple arguments?

I'm trying to select input elements of all type s except radio and checkbox . 5 Answers ...