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# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
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from migrate import ForeignKeyConstraint
import sqlalchemy as sa

[docs]class ForeignKeyHandle(object): def __init__(self, meta): sample = sa.Table('sample', meta, autoload=True) meter = sa.Table('meter', meta, autoload=True) self.sample_params = {'columns': [sample.c.meter_id], 'refcolumns': []} if == 'mysql': self.sample_params['name'] = "fk_sample_meter_id" def __enter__(self): ForeignKeyConstraint(**self.sample_params).drop() def __exit__(self, type, value, traceback): ForeignKeyConstraint(**self.sample_params).create()
def upgrade(migrate_engine): if == 'sqlite': return meta = sa.MetaData(bind=migrate_engine) sample = sa.Table('sample', meta, autoload=True) with ForeignKeyHandle(meta): # remove stray indexes implicitly created by InnoDB for index in sample.indexes: if in ['fk_sample_meter_id', 'fk_sample_resource_id']: index.drop() sa.Index('ix_sample_meter_id', sample.c.meter_id).create()

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