[odb-users] querying with relationships

[Simón Emmanuel Gutiérrez Brida]

Hi again, I have the following classes

User with

#pragma db id
std::string id;

#pragma db value_not_null
std::vector<std::tr1::shared_ptr<Pattern> > patterns;

Pattern with

#pragma db id
std::string id;
#pragma db map type("XML")       \
             as("TEXT")        \
             to("XMLPARSE(DOCUMENT (?))") \
             from("XMLSERIALIZE(DOCUMENT (?) AS TEXT)")
#pragma db type("XML")
std::string data;
Category pattern_category; (it's an enum)

After compiling with odb I got 3 tables (User, Pattern and User_patterns)

I want to do a query like, get all patterns p from user such that
user.id== user_id and p.category == cattegory.

Again I fail to find any information about how to do this in the manual or
the examples.

Any help will be appreciated