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Python assigning multiple variables to same value? list behavior
...ifferent variables with equal values; they're different names for the same identical value. Variables have types, identities, addresses, and all kinds of stuff like that.
Names don't have any of that. Values do, of course, and you can have lots of names for the same value.
If you give Notorious B...
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:
rails g migration create_rest...
How to create named and latest tag in Docker?
...uilt that image using a Dockerfile and executing docker build and by providing a tag using the -t parameter.
6 Answers
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Cannot delete or update a parent row: a foreign key constraint fails
...dvertisers`
ADD CONSTRAINT `advertisers_ibfk_1` FOREIGN KEY (`advertiser_id`)
REFERENCES `jobs` (`advertiser_id`);
...is actually the opposite to what it should be. As it is, it means that you'd have to have a record in the jobs table before the advertisers. So you need to use:
ALTER T...
How to implement a unique index on two columns in rails
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add_index :subscriptions, [:user_id, :content_id], unique: true
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XPath to find elements that does not have an id or class
How can I get all tr elements without id attribute?
4 Answers
4
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How do I iterate over an NSArray?
I'm looking for the standard idiom to iterate over an NSArray. My code needs to be suitable for OS X 10.4+.
8 Answers
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Control cannot fall through from one case label
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switch (searchType)
{
case "SearchBooks":
Selenium.Type("//*[@id='SearchBooks_TextInput']", searchText);
Selenium.Click("//*[@id='SearchBooks_SearchBtn']");
break;
case "SearchAuthors":
Selenium.Type("//*[@id='SearchAuthors_TextInput']", searchText);
...
how to add records to has_many :through association in rails
...mer.new(params[:customer])
@cust.houses << House.find(params[:house_id])
Or when creating a new house for a customer:
@cust = Customer.new(params[:customer])
@cust.houses.create(params[:house])
You can also add via ids:
@cust.house_ids << House.find(params[:house_id])
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Naming “class” and “id” HTML attributes - dashes vs. underlines [closed]
<div id="example-value"> or <div id="example_value"> ?
8 Answers
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