using contains operator with reference types

[dave]

I have two tables defined as follows

db.define_table('animals', 

            Field('type'),

            format='%(type)s')

db.define_table('zoo', 

            Field('name'), 

            Field('tier', 'reference animals'),

            format='%(name)s' 

            ) 

field type is a column with values like, test 1, test 2, test 3

now if I want to select all the records of table zoo with 'test 2' I can do something like this 

rows = db(db.zoo.tier == "2").select()

but why can't I do something like 

db(db.zoo.tier.contains("2")).select() or

pass a list  ["2", "3"] to the contains operator to get all the records of "test 2" and "test 3"? can you suggest another way of implementing this?

[Massimo Di Pierro]

This

rows = db(db.zoo.tier == 2).select()

is equivalent to

rows = db(db.zoo.tier.belongs([2])).select()

you can do

rows = db(db.zoo.tier.belongs([2, 3])).select()

[dave]

ok that works but I have one other question, how would I use the belongs operator If I want to refer a field by a name for example

instead of rows = db(db.zoo.tier.belongs([2, 3])).select()  I want to do this

               rows = db(db.zoo.tier.belongs(["test 2", "test 3"])).select()  ?

[Niphlod]

you join them first and then you belong() on the type column.

db(
    (db.zoo.tier == db.animals.id) &
    (db.animals.type.belongs(['test1', 'test2']))
).select(db.zoo.ALL)

[dave]

is there another way to do it, because this replaces my db.zoo.tier field with the id

[Niphlod]

ehm... mine was an example. You can include in the select what you want from the animals table....

[dave]

Ok got it thank you very much