create_primary_key
create_primary_key(constraint_name: Optional[str], table_name: str, columns: List[str], schema: Optional[str] = None) → Optional[Table]
Issue a “create primary key” instruction using the current migration context.
e.g.:
from alembic import op
op.create_primary_key(
"pk_my_table", "my_table",
["id", "version"]
)
This internally generates a Table object containing the necessary columns, then generates a new PrimaryKeyConstraint object which it then associates with the Table. Any event listeners associated with this action will be fired off normally. The AddConstraint construct is ultimately used to generate the ALTER statement.
Parameters:
- constraint_name – Name of the primary key constraint. The
name
is necessary so that an ALTER statement can be emitted. For setups that use an automated naming scheme such as that described at Configuring Constraint Naming Conventionsname
here can beNone
, as the event listener will apply thename
to the constraint object when it is associated with the table. - table_name – String name of the target table.
- columns – a list of string column names to be applied to the primary key constraint.
- schema – Optional schema name to operate within. To control quoting of the schema outside of the default behavior, use the SQLAlchemy construct quoted_name.