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How to have conditional elements and keep DRY with Facebook React's JSX?
How do I optionally include an element in JSX? Here is an example using a banner that should be in the component if it has been passed in. What I want to avoid is having to duplicate HTML tags in the if statement.
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How to conditionally push an item in an observable array?
...ervableArray , but only if the item is not already present. Is there any "find" function or recommended pattern for achieving this in KnockoutJS?
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How to Store Historical Data
Some co-workers and I got into a debate on the best way to store historical data. Currently, for some systems, I use a separate table to store historical data, and I keep an original table for the current, active record. So, let's say I have table FOO. Under my system, all active records will go ...
How to get last N records with activerecord?
With :limit in query, I will get first N records. What is the easiest way to get last N records?
14 Answers
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How to check existence of user-define table type in SQL Server 2008?
I have a user-defined table type. I want to check it's existence before editing in a patch using OBJECT_ID(name, type) function.
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Rails has_and_belongs_to_many migration
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You need to add a separate join table with only a restaurant_id and user_id (no primary key), in alphabetical order.
First run your migrations, then edit the generated migration file.
Rails 3
rails g migration create_restaurants_users_table
Rails 4...
Can I use view pager with views (not with fragments)
I am using ViewPager for swiping between Fragments , but can I use ViewPager to swipe between Views simple XML layout?
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How to find duplicates in 2 columns not 1
I have a MySQL database table with two columns that interest me. Individually they can each have duplicates, but they should never have a duplicate of BOTH of them having the same value.
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PHP Session Fixation / Hijacking
I'm trying to understand more about PHP Session Fixation and hijacking and how to prevent these problems. I've been reading the following two articles on Chris Shiflett's website:
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Defining a percentage width for a LinearLayout? [duplicate]
I want to define a percentage width (70%) for a LinearLayout that contains some buttons, so that I can center it and so that the child buttons can fill_parent. Here's a picture showing what I mean:
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