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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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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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Partly cherry-picking a commit with Git
...t into unstaged working changes.
Now git stash save --patch: interactively select unwanted material to stash.
Git rolls back the stashed changes from your working copy.
git commit
Throw away the stash of unwanted changes: git stash drop.
Tip: if you give the stash of unwanted changes a name: git ...
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...
Primary key/foreign Key naming convention [closed]
...e the USING syntax in SQL to save some typing and some boilerplate noise:
SELECT name, address, amount
FROM employees JOIN payroll USING (employee_id)
Another argument in favor of convention #2 is that it's the way the relational model was designed.
The significance of each column is
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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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AngularJS - Multiple ng-view in single template
...the content. Here assume you have one main ng-view and instead of manually selecting sub content by selecting drop down, you do it as when main view is loaded.
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Aggregate / summarize multiple variables per group (e.g. sum, mean)
...-date), sum)
# summarising a specific set of non-grouping variables using select_helpers
# see ?select_helpers for more options
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(starts_with('x')), sum)
df2 <- df1 %>% group_by(year, month) %>% summarise_at(vars(matches('.*...
Set transparent background using ImageMagick and commandline prompt
...background color. I just flood fill the background with transparency, then select the alpha channel and blur it and remove half of the blurred area using -level 50x100%. Then turn back on all the channels and flatten it against the brown color. The -blur 0x1 -level 50x100% acts to antialias the bou...
Twitter Bootstrap: Text in navbar
...: Is there a standard Bootstrap class that disable the <p> text from selection?
– Matthew Cornell
Dec 11 '15 at 16:31
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