TypeError: unhashable type: 'dict' when trying to use Sqlalchemy 2.0 syntax

[sahil-kumar-1129]

Hi team, I am currently using fastapi-pagination v0.11.4 and trying to upgrade my sqlalchemy queries to be 2.0 compliant which means converting Query objects to Select objects. This meant I needed to use the paginate function from ext.sqlalchmey_future.py instead of ext.sqlalchemy.py. The migration was going smooth until I need to paginate some queries on table with JSON columns. Then I started receiving the error TypeError: unhashable type: 'dict' trying to return that column by passing my Select query into paginate from ext.sqlalchmey_future.py. Is there a good work around for this issue/if I upgrade the package to a certain version, will it fix this issue and still allow me to continue with my upgrade of the sqlachemy quries?

[uriyyo]

Hi @sahil-kumar-1129,

Could you please try to use unique=False parameter?

[sahil-kumar-1129]

There is no unique parameter. This is the function code:

def paginate( conn: Union[Connection, Engine, Session], query: Select, params: Optional[AbstractParams] = None, ) -> AbstractPage: params = resolve_params(params)

total = conn.scalar(select(func.count()).select_from(query.subquery()))
items = conn.execute(paginate_query(query, params))

return create_page(items.scalars().unique().all(), total, params)

We're using v0.11.4

[uriyyo]

You need to upgrade to latest fastapi-pagination version

[jshields]

I believe we got this working using unique=False with sqlalchemy_future as the paginator on 0.11.4. We are working towards an upgrade path to the latest version. Thank you!

Also noting distinct() is used with the SQLAlchemy select query.

[uriyyo]

Hi @sahil-kumar-1129,

If it's not possible to upgrade to newest version you can use this function:

from typing import Union, Optional, Any

from sqlalchemy import select, func
from sqlalchemy.orm import Session
from sqlalchemy.engine import Engine, Connection
from sqlalchemy.sql import Select

from fastapi_pagination import resolve_params, create_page
from fastapi_pagination.bases import AbstractParams
from fastapi_pagination.ext.sqlalchemy import paginate_query

def paginate(
    conn: Union[Connection, Engine, Session],
    query: Select,
    params: Optional[AbstractParams] = None,
    *,
    unique: bool = True,
) -> Any:
    params = resolve_params(params)

    total = conn.scalar(select(func.count()).select_from(query.subquery()))
    items = conn.execute(paginate_query(query, params))

    if unique:
        items = items.unique()

    return create_page(items.all(), total, params)

[uriyyo]

Any updates? Can I close this issue?

[jshields]

Using unique=False with sqlalchemy_future as the paginator on version 0.11.4, there is no issue. Thanks. This issue can be closed 👍