reorganize docs into sections for easier navigation part 1

docs/models/internals.md

@@ -0,0 +1,70 @@
+# Internals
+
+Apart from special parameters defined in the `Model` during definition (tablename, metadata etc.) the `Model` provides you with useful internals.
+
+## Pydantic Model
+
+All `Model` classes inherit from `pydantic.BaseModel` so you can access all normal attributes of pydantic models.
+
+For example to list pydantic model fields you can:
+
+```Python hl_lines="20"
+--8<-- "../docs_src/models/docs003.py"
+```
+
+!!!tip
+    Note how the primary key `id` field is optional as `Integer` primary key by default has `autoincrement` set to `True`.
+
+!!!info
+    For more options visit official [pydantic][pydantic] documentation.
+
+## Sqlalchemy Table
+
+To access auto created sqlalchemy table you can use `Model.Meta.table` parameter
+
+For example to list table columns you can:
+
+```Python hl_lines="20"
+--8<-- "../docs_src/models/docs004.py"
+```
+
+!!!tip
+    You can access table primary key name by `Course.Meta.pkname`
+
+!!!info
+    For more options visit official [sqlalchemy-metadata][sqlalchemy-metadata] documentation.
+
+## Fields Definition
+
+To access ormar `Fields` you can use `Model.Meta.model_fields` parameter
+
+For example to list table model fields you can:
+
+```Python hl_lines="20"
+--8<-- "../docs_src/models/docs005.py"
+```
+
+!!!info
+    Note that fields stored on a model are `classes` not `instances`.
+    
+    So if you print just model fields you will get:
+    
+    `{'id': <class 'ormar.fields.model_fields.Integer'>, `
+    
+      `'name': <class 'ormar.fields.model_fields.String'>, `
+      
+      `'completed': <class 'ormar.fields.model_fields.Boolean'>}`
+
+
+[fields]: ./fields.md
+[relations]: ./relations/index.md
+[queries]: ./queries.md
+[pydantic]: https://pydantic-docs.helpmanual.io/
+[sqlalchemy-core]: https://docs.sqlalchemy.org/en/latest/core/
+[sqlalchemy-metadata]: https://docs.sqlalchemy.org/en/13/core/metadata.html
+[databases]: https://github.com/encode/databases
+[sqlalchemy connection string]: https://docs.sqlalchemy.org/en/13/core/engines.html#database-urls
+[sqlalchemy table creation]: https://docs.sqlalchemy.org/en/13/core/metadata.html#creating-and-dropping-database-tables
+[alembic]: https://alembic.sqlalchemy.org/en/latest/tutorial.html
+[save status]:  ../models/#model-save-status
+[Internals]:  #internals