Learn to work with one-to-many associations in Rails. These are the most commonly used associations in a typical Rails project. Use these when one person or thing can have many related children records. Define the association in the model using “has_many” and “belongs_to” and then learn how to use association methods in the console.
- [Host] In the last movie,…we saw how to use one-to-one associations.…Now let's build on that…to understand how to work with one-to-many associations.…One-to-many associations are gonna be similar…to one-to-one associations,…but there are a few main differences that I wanna highlight.…First, one-to-many associations…are gonna be much more commonly used.…In a typical application, you'll rarely use one-to-one,…but you'll use one-to-many the most often.…Second, because we have one object related to many objects,…we're gonna use plural names.…That's both gonna be true when we define the association…and also when we call the methods on it.…
We'll see those in a moment.…And third, the relationship…is going to return an array of objects back to us…instead of a single object.…And that just makes sense, right?…If we're going to have many records associated with it,…we're going to have to store those in an array…so that it can hold all of those records.…You use a one-to-many association…when one object has many objects which belong to it,…
Author
Kevin Skoglund
Released
9/28/2016- Creating and configuring a new Ruby on Rails project
- Generating controllers and views
- Handling server requests
- Using different types of routes
- Rendering and viewing templates
- Generating migrations and models
- Creating, updating, and deleting records
- Finding records with queries
- Understanding relationship types
- Writing controllers for CRUD
- Working with layouts and helpers
- Managing application assets
- Building forms
- Validating data
- Authenticating users
Skill Level Beginner
Duration
Views
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Introduction
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Welcome1m 4s
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1. What Is Ruby on Rails?
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2. Get Started
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Create a project7m 3s
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Configure a project10m 15s
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File structure of a project4m 28s
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Access a project3m 38s
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Routes9m 12s
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Experiment on your own1m 17s
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3. Controllers, Views, and Dynamic Content
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Redirect actions6m 4s
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View templates7m 4s
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Instance variables3m 56s
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Links6m 11s
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URL parameters7m 24s
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4. Databases and Migrations
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Introduction to databases7m 53s
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Create a database2m 27s
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Migrations3m 4s
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Generate migrations4m 3s
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Generate models7m 58s
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Run migrations8m 22s
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Migration methods7m 47s
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Solve migration problems5m 41s
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5. Models and ActiveRecord
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Model naming5m 52s
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Model attributes2m 51s
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The Rails console3m 17s
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Create records4m 53s
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Update records3m 16s
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Delete records2m 29s
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Find records5m 48s
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Query methods: Conditions7m 39s
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Named scopes8m 26s
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6. Associations
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Relationship types7m 2s
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One-to-one associations9m 42s
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One-to-many associations7m 54s
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Many-to-many associations: Rich10m 17s
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Traverse a rich association5m 24s
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7. CRUD, REST, and Resourceful Routes
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CRUD6m 56s
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REST5m 51s
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Resourceful routes6m 54s
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Resourceful URL helpers4m 5s
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8. Controllers and CRUD
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Read action: Index6m 31s
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Read action: Show5m 22s
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Form basics5m 13s
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Create action: New4m 54s
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Create action: Create5m 27s
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Strong parameters6m 33s
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Update actions: Edit/update7m 53s
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Flash hash7m 28s
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9. Layouts, Partials, and View Helpers
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Layouts8m 33s
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Partial templates4m 43s
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Text helpers4m 32s
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Number helpers4m 22s
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Date and time helpers3m 39s
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Custom helpers5m 22s
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Sanitization helpers8m 53s
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10. Assets
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Asset pipeline4m 49s
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Stylesheets12m 1s
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JavaScript7m 33s
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Images6m 22s
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11. Forms
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Form helpers8m 35s
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Form options helpers8m 45s
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Date and time form helpers6m 16s
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Form errors7m 36s
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12. Data Validation
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Validation methods11m 37s
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Write validations12m 7s
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Validates method3m 15s
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Custom validations6m 12s
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13. Controller Features
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Cookies3m 10s
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Sessions6m 50s
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Controller filters10m 45s
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Logging7m 40s
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14. User Authentication
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Secure passwords8m 35s
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Login and logout8m 29s
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Restrict access7m 36s
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15. Improve the Simple CMS
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Challenge: AdminUser CRUD2m 44s
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Solution: AdminUser CRUD7m 56s
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Public area10m 35s
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Public area navigation6m 3s
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Nesting pages in subjects9m 44s
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Nesting sections in pages7m 37s
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Finishing touches3m 30s
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Conclusion
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Next steps1m 44s
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Video: One-to-many associations