Ruby/Rails lentelių asociacijos: Skirtumas tarp puslapio versijų
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SNėra keitimo santraukos |
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23 eilutė: | 23 eilutė: | ||
Our project objects are now able to respond to methods such as project.portfolio, project.has_project_manager?, and project.create_in_milestones("deadline" => Date.today + 5). |
Our project objects are now able to respond to methods such as project.portfolio, project.has_project_manager?, and project.create_in_milestones("deadline" => Date.today + 5). |
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But how do we represent many-to-many relationships? Currently, it has the slightly clumsy macro of has_and_belongs_to_many, as illustrated below: |
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class Project < ActiveRecord::Base |
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has_and_belongs_to_many :categories |
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end |
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This makes it possible to do things like project.add_categories(critical, technical) |
13:11, 23 liepos 2005 versija
# projects(id, title) # tasks(id, project_id, title)
Project has_many :tasks
Task belongs_to :project
Kai turime daug su daug sąryšį:
has_and_belongs_to_many
class Project < ActiveRecord::Base belongs_to :portfolio has_one :project_manager has_many :milestones end
Our project objects are now able to respond to methods such as project.portfolio, project.has_project_manager?, and project.create_in_milestones("deadline" => Date.today + 5).
But how do we represent many-to-many relationships? Currently, it has the slightly clumsy macro of has_and_belongs_to_many, as illustrated below:
class Project < ActiveRecord::Base has_and_belongs_to_many :categories end
This makes it possible to do things like project.add_categories(critical, technical)