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- What is the difference between 'reference table' and db.table when you are defining a foreign key?

 

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    anthony 7 years ago

    Generally they are equivalent (behind the scenes, db.table gets converted to 'reference table'). The advantage of the 'reference table' version is that it can be used to refer to tables that have not yet been defined (including self references), whereas the db.table version obviously cannot be used this way.

    replies (3)
    • toomim 7 years ago

      You'd reference a table that hasn't been defined if the table occurs below the definition of the current one.

      Like:

      db.define_table('a', Field('b', 'references b')) db.define_table('b', ...)

      or you can do db.define_table('c', Field('c', 'references c'))

    • costarica 7 years ago
      • Does anyone know a use case of referencing tables that have not yet been defined? I am enjoying so much this framework that I need to know all the good stuff!
    • costarica 7 years ago
      • Why would I want to refererence tables that have not yet been defined (except for self references that I understand)? Thank you.

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