Crop data? If it's featured? The version name? Although I tend to like the approach that you shouldn't solve problems you don't have , this feels different. And I really think that's the kicker. You still have to create the join table.
And that means you have to know the naming convention for that table. By the time you've rediscovered the naming convention, run the migration generator and added the fields, you've likely spent the same amount of time as you would have if you just created a model instead.
Collectives on Stack Overflow. Learn more. Asked 11 years, 6 months ago. Active 2 months ago. Viewed 38k times. John Topley k 45 45 gold badges silver badges bronze badges. Mohit Jain Mohit Jain Add a comment. Active Oldest Votes.
For example, Stories can belong to many categories. Categories can have many stories. For example Person can subscribe to many magazines. Magazines can have many subscribers. TheFooProgrammer 2, 5 5 gold badges 25 25 silver badges 42 42 bronze badges. After making little progress in web development and php I figured out if I can make my grip strong on database designing, I will be able to reduce much code and time in developing the application. But I happen to be a dumb in database designing so can anyone please help to differentiate between has many and belongs to relationship.
They seems quite same to me. Useful for describing 1:n or n:n relationships. Using the 1:n relationship, we are looking at a single object and looking at the 1 or more other objects related to the first object. A parking garage has many cars parked within it. The primary object has many secondary objects. The primary key has many foreign keys linking the primary entry to many other entries in other tables.
Useful for describing or n:1 relationships note that n:1 is the reverse of 1:n, so you're looking at the relationship in the opposite direction. A car belongs to the parking garage. The secondary object belongs to the primary object. A database relationship usually has 2 tables that are linked together.
One table the "belongs to"-side contains a foreign key to the other table the "has many"-side. So most relations have both sides. It is good that you are learning about database design and data modeling.
You may want to cache the counts for your hasMany associations. For example, the comment count on any given article is often cached to make generating lists of articles more efficient.
You can use the CounterCacheBehavior to cache counts of associated records. You should make sure that your database tables do not contain columns that match association property names. If for example you have counter fields that conflict with association properties, you must either rename the association property, or the column name.
The main difference between hasMany and BelongsToMany is that the link between the models in a BelongsToMany association is not exclusive. For example, we are joining our Articles table with a Tags table. I can also use it on the next article I write. Three database tables are required for a BelongsToMany association.
The joining table is named after the two tables involved, separated with an underscore by convention. By default this table name will be used to load the Table instance for the join table. This is especially handy if you need to define multiple belongsToMany relationships. Defaults to the primary key. This makes customizing the join table keys possible, and allows you to customize the behavior of the pivot table.
This defaults to false to help reduce overhead. Indicates the mode to be used for saving associated entities. The former will only create new links between both side of the relation and the latter will do a wipe and replace to create the links between the passed entities when saving. Once this association has been defined, find operations on the Articles table can contain the Tag records if they exist:. The through option provides you full control over how the belongsToMany association will be created.
It is sometimes desirable to store additional data with a many to many association.
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