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POSQLalchemy: Mapping columns into different properties
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copied!<p>I am trying to store some simulation measurements (times and values) using sqlalchemy. Here are the relevant table definitions. If there is a more sensible table definition, I'd love to see it.</p> <pre><code>from sqlalchemy import create_engine, schema, orm engine = create_engine('sqlite:///:memory:', echo=True) metadata = schema.MetaData(bind=engine) container_table = schema.Table('containers', metadata, schema.Column('id', schema.types.Integer, primary_key=True)) measurement_table = schema.Table('measurements', metadata, schema.Column('id', schema.types.Integer, primary_key=True), schema.Column('container_id', schema.types.Integer, schema.ForeignKey('containers.id')), schema.Column('time', schema.types.Float), schema.Column('value', schema.types.Float)) metadata.create_all() </code></pre> <p>The times will be unique for each container, and the below properties should be ordered by time.</p> <p>I would like to be able to both read and assign these properties:</p> <pre><code>c = Container() times = range(10) values = [t**2 for t in times] c.times = times c.values = values </code></pre> <p>But I don't know how to do the mapping. I assume that if it's possible, it will look something like this:</p> <pre><code>class Container(object): times = some_sort_of_proxy() values = some_sort_of_proxy() orm.mapper(Container, container_table, properties={ # Magic }) </code></pre> <p>How do I go about doing this? Is this a reasonable mapping, or do I need to have a different underlying table structure?</p>

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