class Author {
Map books // map of ISBN:book names
}
def a = new Author()
a.books = ["1590597583":"Grails Book"]
a.save()
Can anyone can explain, how Author Table will look and what relation to Book,
That's rather not possible, I would do a List of other objects (or hasMany relation), eg
class Book {
String isbn
String title
}
that's more flexible and extensible comparing to a Map.Entry where you are limited to key and value, and you can't add any other property
Grails will create a table for you called author
that will look like this:
id | version
1 | 1
2 | 2
...
You will also get another table called author_books
that contains key-value pairs from your books
map and looks like this:
books | books_idx | books_elt
authorId | someKey | someValue
As @Kamil Mikolajczyk says though, your model will usually be easier to understand if you use a collection of Book
objects.
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