Can I assign values in RowProxy using the sqlalchemy?

Question

When I want to display some data in the web, the data need makeup, and I don\'t know how to achieve, here is the code:

from sqlalchemy import create_engine

         


        

Answer 1

One nice trick with this is to use a subclass of a dict:

class DBRow(dict):
    def __getattr__(self, key):
        """make values available as attributes"""
        try:
            return self[key]
        except KeyError as error:
            raise AttributeError(str(error))

   @property
   def something_calculated(self):
       return self.a + self.b

row = DBRow(result_proxy_row, additional_value=123)
row["b"] = 2 * row.b
print something_calculated

The benefit of this is, that you can access the values still as attributes, plus you can have properties, which is a nice way to cleanup and massage the data coming from the database.

Answer 2

You can make a dict out of your RowProxy, which would support item assignment.

For example:

result_proxy = query.fetchall()
for row in result_proxy:
    d = dict(row.items())
    d['Tags'] = d['Keywords']