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Code First: Independent associations vs. Foreign key associations?
...ays generate entity references. If you don't want to use them you must manually modify the EDMX file and add properties representing FKs. At least this was the case in Entity Framework v1 where only Independent associations were allowed.
Entity framework v4 offers a new type of association called F...
Are SVG parameters such as 'xmlns' and 'version' needed?
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All user agents (browsers) ignore the version attribute, so you can always drop that.
If you embed your SVG inline in a HTML page and serve that page as text/html then xmlns attributes are not required. Embedding SVG inline ...
What are the obj and bin folders (created by Visual Studio) used for?
...ich are compiled binary files that haven't been linked yet. They're essentially fragments that will be combined to produce the final executable. The compiler generates one object file for each source file, and those files are placed into the obj folder.
The bin folder holds binary files, which are ...
What is causing ERROR: there is no unique constraint matching given keys for referenced table?
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In postgresql all foreign keys must reference a unique key in the parent table, so in your bar table you must have a unique (name) index.
See also http://www.postgresql.org/docs/9.1/static/ddl-constraints.html#DDL-CONSTRAINTS-FK and speci...
What are good alternatives to SQL (the language)? [closed]
I occasionally hear things about how SQL sucks and it's not a good language, but I never really hear much about alternatives to it. So, are other good languages that serve the same purpose (database access) and what makes them better than SQL? Are there any good databases that use this alternative l...
Simple calculations for working with lat/lon and km distance?
...long coordinates are expressed in degrees, while the cos function in most (all?) languages typically accepts radians, therefore a degree to radians conversion is needed.
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Using bitwise OR 0 to floor a number
...ator casts the
number to an integer, thus removing the fractional part
All bitwise operations except unsigned right shift, >>>, work on signed 32-bit integers. So using bitwise operations will convert a float to an integer.
Does it have any advantages over doing Math.floor? Maybe it...
Conda: Installing / upgrading directly from github
Can I install/upgrade packages from GitHub using conda ?
4 Answers
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Change a column type from Date to DateTime during ROR migration
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This answer is only partially correct, you can not use change_column inside change even on rails 4 or down migration will not work. You should use up/down no matter the version of rails.
– Alan Peabody
Jul 18 '1...
Ajax using https on an http page
...d https protocol; it doesn't affect the content. My site uses jQuery ajax calls, which fills some areas on the page, too.
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