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How to check if a model has a certain column/attribute?
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For bonus points use Hash#select: number_hash.select { |key, value| Number.column_names.include? key }
– hgmnz
Nov 10 '09 at 18:31
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How was the first compiler written?
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What wrote the first compiler that converted something into binary instructions?
A human did. Read about the A-0 system:
In 1952, Grace Hopper completed her first compiler for Sperry, known as the A-0. The A-0 System was a set of instructions that could ...
How to capitalize the first character of each word in a string
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The following method converts all the letters into upper/lower case, depending on their position near a space or other special chars.
public static String capitalizeString(String string) {
char[] chars = string.toLowerCase().toCharArray();
b...
ERROR 2006 (HY000): MySQL server has gone away
...L/MariaDB server.
Double check the value was set properly by:
mysql -sve "SELECT @@max_allowed_packet" # or:
mysql -sve "SHOW VARIABLES LIKE 'max_allowed_packet'"
You got a timeout from the TCP/IP connection on the client side.
Solution: Increase wait_timeout variable.
You tried to run a query a...
Automatic creation date for Django model form objects?
...t do that (the database needs something to populate existing rows). Please select a fix: 1) Provide a one-off default now (will be set on all existing rows) 2) Quit, and let me add a default in models.py Select an option: 1 Please enter the default value now, as valid Python The datetime and djang...
Changing Ctrl + Tab behavior for moving between documents in Visual Studio
...w place cursor in the Press shortcut keys: textbox (doesn't matter what is selected currently, you're not going to Assign this time), and type first of the three (or two or one) shortcuts.
You'll see Shortcut currently used by: listed. Ensure that you have no duplicate entry for the shortcut. In...
Why do I get the error “Unsafe code may only appear if compiling with /unsafe”?
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For everybody who uses Rider you have to select your project>Right Click>Properties>Configurations Then select Debug and Release and check "Allow unsafe code" for both.
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Black transparent overlay on image hover with only CSS?
...-filters/
Similar topics on SO
How to Decrease Image Brightness in CSS
Convert an image to grayscale in HTML/CSS
Defined Edges With CSS3 Filter Blur
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Change a Git remote HEAD to point to something besides master
...inking about these specific services.
Now they have a drop-down menu for selecting the HEAD branch at http://repo.or.cz (example: http://repo.or.cz/editproj.cgi?name=for-me-and-for-all_imz.git);
and at http://gitorious.org, too (look somewhere in the settings);
and at http://GitHub.com: admin >...
UINavigationController without navigation bar?
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In Xcode 4.3.2:
Select the navigation controller in the storyboard
Select the Attributes Inspector in the (right) Utilities panel
Under the Navigation Controller category you have two check boxes:
[] Shows Navigation Bar
[] Shows Toolbar
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