SQLAlchemy Composite Column Type Not working

[erenz14]

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Example Code

from sqlmodel import SQLModel, Field
from sqlalchemy.orm import composite
from typing import Optional

class Point(object):
    def __init__(self, x, y):
        self.x = x
        self.y = y

    def __composite_values__(self):
        return self.x, self.y

    def __repr__(self):
        return f"Point(x={self.x!r}, y={self.y!r})"

    def __eq__(self, other):
        return isinstance(other, Point) and other.x == self.x and other.y == self.y

    def __ne__(self, other):
        return not self.__eq__(other)

class Vertex(SQLModel, table=True):

    id = Optional[int] = Field(default=None, primary_key=True)
    x1: int = Field(default=None)
    y1: int = Field(default=None)
    x2: int = Field(default=None)
    y2: int = Field(default=None)

    start = composite(Point, x1, y1)
    end = composite(Point, x2, y2)

Description

SQLAlchemy describes the Composite Column Type here: https://docs.sqlalchemy.org/en/14/orm/composites.html

I'm trying to use Composite Column Type with SQLModel in a similar way as show above in the example, but I receive the following error: TypeError: cannot pickle 'property' object

Has anybody successfully used the composite column type with SQLModel yet?

Operating System

Windows

Operating System Details

No response

SQLModel Version

0.0.8

Python Version

3.8.0

Additional Context

No response

[jpmckinney]

I have a similar question, in that SQLModel doesn't seem to support multicolumn indexes? I suppose I need to drop down to SQLAlchemy or Alembic to add a multicolumn index.