Module: Foreigner::ConnectionAdapters::SQLServerAdapter

Includes:
Sql2003
Defined in:
lib/sqlserver/foreigner/sqlserver-adapter.rb

Instance Method Summary collapse

Instance Method Details

#foreign_keys(table_name) ⇒ Object 



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# File 'lib/sqlserver/foreigner/sqlserver-adapter.rb', line 6

def foreign_keys(table_name)
  # Called from schema_dump
  fk_info = select_all %{
    SELECT  to_table.name AS to_table,
            -- from_table.name AS from_table,
            from_column.name AS from_column,
            to_column.name AS primary_key,
            foreign_key.name AS name,
            CASE WHEN foreign_key.status & 4096 <> 0
            THEN 'c' ELSE 'r'
            END AS dependency
    FROM    sysobjects AS from_table,
            sysforeignkeys AS f,
            sysobjects AS to_table,
            sysobjects AS foreign_key,
            syscolumns AS from_column,
            syscolumns AS to_column
    WHERE   from_table.type = 'U'
      AND   from_table.id = f.fkeyid
      AND   f.constid = foreign_key.id
      AND   f.rkeyid = to_table.id
      AND   f.fkey = from_column.colid
      AND   from_column.id = from_table.id
      AND   f.rkey = to_column.colid
      AND   to_column.id = to_table.id
      AND   from_table.name = '#{table_name}'
    ORDER BY from_table.name, to_table.name, foreign_key.name, from_column.name
  }

  fk_info.map do |row|
    options = {:column => row['from_column'], :name => row['name'], :primary_key => row['primary_key']}

    options[:dependent] = case row['dependency']
      when 'c' then :delete
      when 'n' then :nullify    # Not currently extracted
      #when 'r' then :restrict
    end

    ForeignKeyDefinition.new(table_name, row['to_table'], options)
  end
end