Rails update attributes not updating

Nested attributes allow you to save attributes on associated records through the parent.

By default nested attribute updating is turned off and you can enable it using the #accepts_nested_attributes_for class method.

When you enable nested attributes an attribute writer is defined on the model.

rails update attributes not updating-61rails update attributes not updating-14

By default the associated records are protected from being destroyed.

If you want to destroy any of the associated records through the attributes hash, you have to enable it first using the for one of such keys, otherwise the hash will be wrapped in an array and interpreted as an attribute hash for a single post.

Passing attributes for an associated collection in the form of a hash of hashes can be used with hashes generated from HTTP/HTML parameters, where there may be no natural way to submit an array of hashes.

All changes to models, including the destruction of those marked for destruction, are saved and destroyed automatically and atomically when the parent model is saved.

This happens inside the transaction initiated by the parent's save method. If you want to validate that a child record is associated with a parent record, you can use the option, then Active Record will try to automatically guess the inverse association based on heuristics.

For one-to-one nested associations, if you build the new (in-memory) child object yourself before assignment, then this module will not overwrite it, e.g.: Allows you to specify a Proc or a Symbol pointing to a method that checks whether a record should be built for a certain attribute hash.

The hash is passed to the supplied Proc or the method and it should return either Allows you to specify the maximum number of associated records that can be processed with the nested attributes.

Limit also can be specified as a Proc or a Symbol pointing to a method that should return a number.

If the size of the nested attributes array exceeds the specified limit, Nested Attributes:: Too Many Records exception is raised.

If omitted, any number of associations can be processed.

Note that the For a one-to-one association, this option allows you to specify how nested attributes are going to be used when an associated record already exists.

Tags: , ,