如何使用sqlalchemy add_all在Fast API中大容量保存

Question

我正在尝试将患者批量添加到数据库中，但遇到了一个错误。 目标是从请求体读取数据，截断表中的数据并添加新数据。 有人能告诉我我做错了什么吗

代码

schemas.py

from pydantic import BaseModel
from typing import Optional

class PatientBase(BaseModel):
    ticket_id: str
    patient_name: Optional[str] = None



class PatientInDb(PatientBase):
    patient_id : str
    institute :str

    class Config:
        orm_mode = True

crud.py

from typing import List
from sqlalchemy.orm import Session

def create_patients(db: Session, patients: List[schemas.PatientInDb] ):
    num_of_deleted_rows = db.query(models.Patient).delete()

    db.add_all(patients)
    db.commit()
    return db.query(models.Patient).count()

patients.py

@router.post("/patients")
async def post_patients(
    patients : List[schemas.PatientInDb],
    db: Session = Depends(get_db),
    
):
    patients_count = crud.create_patients(db, patients)
    return {
        "message":f"New {patients_count} patients created."
    }

错误

  File ".\app\api\v1\patients.py", line 45, in post_patients
    patients_count = crud.create_patients(db, patients)
  File ".\app\crud.py", line 13, in create_patients
    db.add_all(patients)
  File "c:\users\convergytics\miniconda3\envs\test\lib\site-packages\sqlalchemy\orm\session.py", line 2016, in add_all
    for instance in instances:
  File "c:\users\convergytics\miniconda3\envs\test\lib\typing.py", line 682, in inner
    return func(*args, **kwds)
  File "c:\users\convergytics\miniconda3\envs\test\lib\typing.py", line 1107, in __getitem__
    params = tuple(_type_check(p, msg) for p in params)
  File "c:\users\convergytics\miniconda3\envs\test\lib\typing.py", line 1107, in <genexpr>
    params = tuple(_type_check(p, msg) for p in params)
  File "c:\users\convergytics\miniconda3\envs\test\lib\typing.py", line 374, in _type_check
    raise TypeError(msg + " Got %.100r." % (arg,))
TypeError: Parameters to generic types must be types. Got 0.

Answer 1

在文件“patients.py”中

更改：

"patients = List[schemas.PatientInDb]" 

到

"patients: List[schemas.PatientInDb]" 

原因“=”用于指定默认值，“：”用于引用类型

Answer 2

您在discord上也得到了这个答案，但是您正在保存pydantic模型，而不是sqlalchemy模型