Joins and table names in ferret

I’m having trouble figuring out how to do Ferret queries across multiple
tables as you would in a normal SQL call. For example, let’s say I have
two ActiveRecord classes, Book, and Author, where Book has a
‘description’ field and Author has a ‘name’ field, and where Book has a
belongs_to relationship with Author (Book belolngs to Author, Author
has_many Books). Let’s say I’d like to find all Books with the term
‘programming’ in their description that are by people with ‘Smith’ in
their name. I’d like to do something like this:

Book.find_by_contents(“books.description:programming AND
authors.name:Smith”,
{},
{:include => :author})

However, this function does not seem to allow the specification of table
names. This type of call would be relatively easy in plain SQL, but I’d
like to use Ferret for all queries to keep things uniform and to take
advantage of its speed. I’ve looked into using the multi_search option
also, but can’t figure out how to use it to do even simple joins such as
this one. Any help would be greatly appreciated. Thanks.

I realized that I wasn’t fully clear in this example…I would want
returned all Book objects where the Book description contains the word
‘programming’, the Author name contains the word ‘Smith’, AND (what I
didn’t explicitly say before) the book is by that author. So more
informally, I want to find all programming books who are by someone with
‘Smith’ in their name. This would amount to the extra join statment of
‘books.author_id=author.id’. I’m having a really hard time figure out
how to do this in Ferret (using acts_as_ferret).

Jon wrote:

I’m having trouble figuring out how to do Ferret queries across multiple
tables as you would in a normal SQL call. For example, let’s say I have
two ActiveRecord classes, Book, and Author, where Book has a
‘description’ field and Author has a ‘name’ field, and where Book has a
belongs_to relationship with Author (Book belolngs to Author, Author
has_many Books). Let’s say I’d like to find all Books with the term
‘programming’ in their description that are by people with ‘Smith’ in
their name. I’d like to do something like this:

Book.find_by_contents(“books.description:programming AND
authors.name:Smith”,
{},
{:include => :author})

However, this function does not seem to allow the specification of table
names. This type of call would be relatively easy in plain SQL, but I’d
like to use Ferret for all queries to keep things uniform and to take
advantage of its speed. I’ve looked into using the multi_search option
also, but can’t figure out how to use it to do even simple joins such as
this one. Any help would be greatly appreciated. Thanks.

On 10/19/06, Jon [email protected] wrote:

I’m having trouble figuring out how to do Ferret queries across multiple
{},
{:include => :author})

However, this function does not seem to allow the specification of table
names. This type of call would be relatively easy in plain SQL, but I’d
like to use Ferret for all queries to keep things uniform and to take
advantage of its speed. I’ve looked into using the multi_search option
also, but can’t figure out how to use it to do even simple joins such as
this one. Any help would be greatly appreciated. Thanks.

Hi Jon,

Ferret isn’t a database (yet?[1]). If you need to run queries like
this then you should index the author name in the book document and
forget about doing joins for the moment. Queries will be a lot faster
this way too. I think this is pretty easy in acts as ferret. Just
define the method author_names

def author_names
    authors.map{|author| author.name}
end

And make sure :author_names is in your list of fields to index.

Cheers,
Dave

[1] http://www.mail-archive.com/[email protected]/msg01183.html

Thanks a ton for the quick reply…very much appreciated. And thanks
for the great software as well.

David B. wrote:

On 10/19/06, Jon [email protected] wrote:

I’m having trouble figuring out how to do Ferret queries across multiple
{},
{:include => :author})

However, this function does not seem to allow the specification of table
names. This type of call would be relatively easy in plain SQL, but I’d
like to use Ferret for all queries to keep things uniform and to take
advantage of its speed. I’ve looked into using the multi_search option
also, but can’t figure out how to use it to do even simple joins such as
this one. Any help would be greatly appreciated. Thanks.

Hi Jon,

Ferret isn’t a database (yet?[1]). If you need to run queries like

This forum is not affiliated to the Ruby language, Ruby on Rails framework, nor any Ruby applications discussed here.

| Privacy Policy | Terms of Service | Remote Ruby Jobs