Below is a preview of GORM in action: In this case the underlying Hibernate engine will not do any dirty checking and the object will not be persisted.
Note that if you explicitly call the save method then the object is placed back into a read-write state.
If you are validating user-submitted data that's been bound to some domain object, then in order to check for the save failing due to invalid input the idiomatic thing to do is check the return value of save; failing on account of invalid input is not exceptional behavior.
I have an application using grails 2.5.1 I am trying to update multiple domain objects of the same type from a list.
You have to be able to migrate the schema and also any existing data.
The database migration plugin allows you to keep track of the structural changes made to your database.
They are linked together through relationships; one-to-one, one-to-many, or many-to-many.
That's what the "mem" in your url string refers to.
I find it easier, especially w/ a small project to use Boot Strap.groovy in combination w/ db Create="create-drop".
GORM is Grails' object relational mapping (ORM) implementation.
Under the hood it uses Hibernate (a very popular and flexible open source ORM solution) and thanks to the dynamic nature of Groovy with its static and dynamic typing, along with the convention of Grails, there is far less configuration involved in creating Grails domain classes. See the section on Hibernate Integration for how to write domain classes in Java but still use dynamic persistent methods.