I found 2 additional issues related to naming conventions:

1. A bug from SQLAlchemy: Using naming convention token referred_column_0_name raises sqlalchemy.exc.NoReferencedColumnError sqlalchemy/sqlalchemy#7958

   There's a bug when using referrenced table's columns in naming convention (e.g., %(referred_column_0_name)s", %(referred_column_0_N_name)s") together with ForeignKey. The tokens work fine using the ForeignKeyConstraint though.

   The bug fix will be released in 1.4.36, but this means we'll have a check of SQLAlchemy version:

   • For versions <1.4.36, we should use a nameless ForeignKeyConstraint instead of ForeignKey directly in Column when uses_default_name is True
   • For versions >=1.4.36 we should have the expeced behavior of using ForeignKey directly in Column when uses_default_name is True

2. The naming convention token %(constraint_name)s

   We're not currently handling the token uses_default_name correctly. It's best to illustrate this with an example:

   Consider the following test case (copied from Add constraint naming convention configuration option #197):

   def test_constraint_name_token(self, generator: CodeGenerator) -> None:
       generator.metadata.naming_convention = {
           "ck": "ck_%(table_name)s_%(constraint_name)s",
           "pk": "pk_%(table_name)s",
       }
   
       Table(
           "simple",
           generator.metadata,
           Column("id", INTEGER),
           Column("number", INTEGER),
           PrimaryKeyConstraint("id", name="pk_simple"),
           CheckConstraint("id > 0", name=conv("ck_simple_idcheck")),
           CheckConstraint("number > 0", name=conv("non_default_name")),
       )

   Current output:

   from sqlalchemy import CheckConstraint, Column, Integer
   from sqlalchemy.orm import declarative_base
   
   Base = declarative_base()
   Base.metadata.naming_convention = {'ck': 'ck_%(table_name)s_%(constraint_name)s', 'pk': 'pk_%(table_name)s'}
   
   
   class Simple(Base):
       __tablename__ = 'simple'
       __table_args__ = (
           CheckConstraint('id > 0', name='ck_simple_idcheck'),
           CheckConstraint('number > 0', name='non_default_name')
       )
   
       id = Column(Integer, primary_key=True)
       number = Column(Integer

   Expected output is:

   from sqlalchemy import CheckConstraint, Column, Integer, MetaData
   from sqlalchemy.orm import declarative_base
   from sqlalchemy.sql.elements import conv
   
   Base = declarative_base()
   Base.metadata.naming_convention = {'ck': 'ck_%(table_name)s_%(constraint_name)s', 'pk': 'pk_%(table_name)s'}
   
   
   class Simple(Base):
       __tablename__ = 'simple'
       __table_args__ = (
           CheckConstraint('id > 0', name='idcheck'),
           CheckConstraint('number > 0', name=conv('non_default_name'))
       )
   
       id = Column(Integer, primary_key=True)
       number = Column(Integer)

   There are 2 things to do here:

   • uses_default_name must be fixed to be able to handle constraint_name correctly
   • For contraints whose naming convention contains %(constraint_name)s, if the name of that constraint does not fit the naming convention (i.e., uses_default_name is False), it must be marked with sqlalchemy.sql.elements.conv

Since we already require SQLAlchemy 1.4 in the latest release, we can just bump the minimum version requirement to 1.4.36 and not have to add any workarounds.

SQLAlchemy 1.4.36 was released an hour ago so I've pushed changes to set the minimum sqla requirement to that now. Should address the first issue you described.