Files
superset2/superset/migrations/migration_utils.py
2025-04-14 19:01:11 -07:00

60 lines
2.3 KiB
Python

# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
from alembic.operations import Operations
from sqlalchemy.engine.reflection import Inspector
naming_convention = {
"fk": "fk_%(table_name)s_%(column_0_name)s_%(referred_table_name)s",
"uq": "uq_%(table_name)s_%(column_0_name)s",
}
def create_unique_constraint(
op: Operations, index_id: str, table_name: str, uix_columns: list[str]
) -> None:
# Get the database connection and inspector
bind = op.get_bind()
inspector = Inspector.from_engine(bind)
# Check if the unique constraint already exists
existing_constraints = inspector.get_unique_constraints(table_name)
for constraint in existing_constraints:
if constraint["name"] == index_id:
# Constraint already exists, no need to create it
return
# Create the unique constraint if it doesn't exist
with op.batch_alter_table(
table_name, naming_convention=naming_convention
) as batch_op:
batch_op.create_unique_constraint(index_id, uix_columns)
def drop_unique_constraint(op: Operations, index_id: str, table_name: str) -> None:
dialect = op.get_bind().dialect.name
with op.batch_alter_table(
table_name, naming_convention=naming_convention
) as batch_op:
if dialect == "mysql":
# MySQL requires specifying the type of constraint
batch_op.drop_constraint(index_id, type_="unique")
else:
# For other databases, a standard drop_constraint call is sufficient
batch_op.drop_constraint(index_id)