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"""Migrate negative weights
Revision ID: a67119aa3ee5
Revises: afbf27e6ef20
Create Date: 2018-12-25 18:34:20.220844
"""
# revision identifiers, used by Alembic.
revision = 'a67119aa3ee5'
down_revision = 'afbf27e6ef20'
from alembic import op
import sqlalchemy as sa
# Snapshot of the person table
person_helper = sa.Table(
'person', sa.MetaData(),
sa.Column('id', sa.Integer(), nullable=False),
sa.Column('project_id', sa.String(length=64), nullable=True),
sa.Column('name', sa.UnicodeText(), nullable=True),
sa.Column('activated', sa.Boolean(), nullable=True),
sa.Column('weight', sa.Float(), nullable=True),
sa.ForeignKeyConstraint(['project_id'], ['project.id'], ),
sa.PrimaryKeyConstraint('id')
)
def upgrade():
op.execute(
person_helper.update()
.where(person_helper.c.weight <= 0)
.values(weight=1)
)
def downgrade():
# Downgrade path is not possible, because information has been lost.
pass
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