gable-tutorial/db_migrations/versions/break_gable.py at main · ilinardic22/gable-tutorial · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
"""order_detail changes

Revision ID: 7a341d712aa5
Revises: 78da3a78bfd6
Create Date: 2023-09-29 13:22:35.204135

"""
from typing import Sequence, Union

from alembic import op
import sqlalchemy as sa


# revision identifiers, used by Alembic.
revision: str = '7a341d712aa5'
down_revision: Union[str, None] = '78da3a78bfd6'
branch_labels: Union[str, Sequence[str], None] = None
depends_on: Union[str, Sequence[str], None] = None


def upgrade() -> None:
    # Make the vendor optional
    op.alter_column(
        'order_details',
        'vendor_id',
        nullable=True,
    )

    # Convert existing values to integers (for example, if representing cents)
    op.execute('UPDATE order_details SET unit_price = ROUND(unit_price * 100)')
    op.execute('UPDATE order_details SET total_price = ROUND(total_price * 100)')

    # Alter the column type
    op.alter_column('order_details', 'unit_price', type_=sa.Integer)
    op.alter_column('order_details', 'total_price', type_=sa.Integer)


def downgrade() -> None:
    op.alter_column(
        'order_details',
        'vendor_id',
        nullable=False,
    )

    # Alter the column type back to Numeric
    op.alter_column('order_details', 'unit_price', type_=sa.Numeric(10, 2))
    op.alter_column('order_details', 'total_price', type_=sa.Numeric(10, 2))

    # Convert integer values back to their decimal representations
    op.execute('UPDATE order_details SET unit_price = total_price / 100.0')
    op.execute('UPDATE order_details SET total_price = total_price / 100.0')