🎨 Fix nullable property of Fields

Author: van51

sqlmodel/main.py

@@ -26,6 +26,7 @@
 
 from pydantic import BaseModel
 from pydantic.errors import ConfigError, DictError
+from pydantic.fields import SHAPE_SINGLETON
 from pydantic.fields import FieldInfo as PydanticFieldInfo
 from pydantic.fields import ModelField, Undefined, UndefinedType
 from pydantic.main import BaseConfig, ModelMetaclass, validate_model
@@ -414,7 +415,7 @@ def get_column_from_field(field: ModelField) -> Column:
         return sa_column
     sa_type = get_sqlachemy_type(field)
     primary_key = getattr(field.field_info, "primary_key", False)
-    nullable = not field.required
+    nullable = not primary_key and _is_field_nullable(field)
     index = getattr(field.field_info, "index", Undefined)
     if index is Undefined:
         index = True
@@ -634,3 +635,13 @@ def _calculate_keys(  # type: ignore
     @declared_attr  # type: ignore
     def __tablename__(cls) -> str:
         return cls.__name__.lower()
+
+
+def _is_field_nullable(field: ModelField) -> bool:
+    if not field.required:
+        # Taken from [Pydantic](https://github.com/samuelcolvin/pydantic/blob/v1.8.2/pydantic/fields.py#L946-L947)
+        is_optional = field.allow_none and (
+            field.shape != SHAPE_SINGLETON or not field.sub_fields
+        )
+        return is_optional and field.default is None and field.default_factory is None
+    return False

tests/test_tutorial/test_create_db_and_table/test_tutorial001.py

@@ -9,7 +9,7 @@ def test_create_db_and_table(cov_tmp_path: Path):
     assert "BEGIN" in result.stdout
     assert 'PRAGMA main.table_info("hero")' in result.stdout
     assert "CREATE TABLE hero (" in result.stdout
-    assert "id INTEGER," in result.stdout
+    assert "id INTEGER NOT NULL," in result.stdout
     assert "name VARCHAR NOT NULL," in result.stdout
     assert "secret_name VARCHAR NOT NULL," in result.stdout
     assert "age INTEGER," in result.stdout