24 lines
532 B
Python
24 lines
532 B
Python
from sqlalchemy import Column, Integer, ForeignKey
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from platypush.common.db import Base
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from .sensors import NumericSensor
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if 'time_duration' not in Base.metadata:
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class TimeDuration(NumericSensor):
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"""
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An entity that measures a time duration.
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"""
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__tablename__ = 'time_duration'
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id = Column(
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Integer, ForeignKey(NumericSensor.id, ondelete='CASCADE'), primary_key=True
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)
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__mapper_args__ = {
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'polymorphic_identity': __tablename__,
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}
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