SQLModel's Field is needs to update the name of a param for compatibility with Pydantic.

[lwashington3]

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Example Code

import re
import sqlmodel


ORCID_REGEX = re.compile(r"([\dX]{4}-[\dX]{4}-[\dX]{4}-[\dX]{4})")


class Author(sqlmodel.SQLModel, table=False):
	name: str = sqlmodel.Field(description="The name of the author.")

	orcid: Optional[str] = sqlmodel.Field(
		default=None,
		description="The author's ORCID iD, if available.",
		regex=r"([\dX]{4}-[\dX]{4}-[\dX]{4}-[\dX]{4})"
	)

	def __repr__(self) -> str:
		if self.orcid is None:
			return f"Author({self.name})"
		return f"Author({self.name}, orcid={self.orcid})"

	def __hash__(self) -> int:
		if self.orcid is not None:
			return hash(self.orcid)
		return hash(self.name)

	def __eq__(self, other, /) -> bool:
		if isinstance(other, str):
			return self.name == other
		elif not isinstance(other, self.__class__):
			return False
		if other.orcid is not None:
			return self.orcid == other.orcid
		return self.name == other.name

Description

Pydantic's Field changed the parameter name of regex to pattern, so the value given to regex isn't being used by Pydantic.

Operating System

Linux

Operating System Details

Docker image base: python:3.14.4-slim

Project Version

0.0.38

Python Version

3.14.4

Additional Context

pydantic==2.13.4
pydantic_settings==2.14.2

[Kxrma47]

You are right about the compatibility gap. SQLModel's current Field overloads still expose regex, while Pydantic v2 uses pattern, so relying on regex here can fail to create the validation constraint you expect. Until SQLModel accepts and forwards pattern directly, a clean Pydantic-v2 workaround is to put the constraint on the type: define Orcid = Annotated[str, StringConstraints(pattern=r"^[\dX]{4}-[\dX]{4}-[\dX]{4}-[\dX]{4}$")] and annotate the field as orcid: Orcid | None = Field(default=None, description=...). Anchoring the expression is also important; otherwise a valid-looking substring inside a longer invalid value can match. This keeps runtime validation and generated JSON Schema aligned without depending on SQLModel's legacy regex parameter. The long-term fix should add pattern to SQLModel Field's overloads and implementation, pass it to Pydantic FieldInfo, and deprecate regex in a version-compatible way rather than silently renaming it, since existing applications may still depend on the old argument.

[YuriiMotov]

We already have PR for this: #1231
It's awaiting Sebastian's review