Using try_cast in SQLAlchemy

[dwolfeu]

Expected behavior

sqlalchemy.sql.try_cast should work.

Actual behavior

It doesn't work.

Steps To Reproduce

from sqlalchemy import create_engine, Column, Integer, String, select, try_cast
from sqlalchemy.orm import declarative_base, Session
from trino.auth import OAuth2Authentication

engine = create_engine(
'<url-of-trino-server>',
    connect_args={
        'auth': OAuth2Authentication(),
        'http_scheme': 'https',
        'catalog': '<catalog-name>'
    }
)

Base = declarative_base()

class MyTable(Base):
    __tablename__ = 'foobar'
    __table_args__ = {'schema': 'baz'}
    id = Column(Integer, primary_key=True)

session = Session(engine)
stmt = select(try_cast(MyTable.id,String)).where(MyTable.id.in_([1,2,3]))

for i in session.scalars(stmt):
    print(i)

Log output

AttributeError: 'TrinoSQLCompiler' object has no attribute 'visit_try_cast'

The above exception was the direct cause of the following exception:

# <Lots of detailed error messages>

UnsupportedCompilationError: Compiler <trino.sqlalchemy.compiler.TrinoSQLCompiler object at 0x1696e8d60> can't render element of type <class 'sqlalchemy.sql.elements.TryCast'> (Background on this error at: https://sqlalche.me/e/20/l7de)

Operating System

macOS Sonoma 14.5

Trino Python client version

0.329.0

Trino Server version

426

Python version

3.10.2

Are you willing to submit PR?

• Yes I am willing to submit a PR!

[dwolfeu]

https://stackoverflow.com/questions/78764465/invoking-trinos-try-cast-using-sqlalchemy