我想创建 python SQLAlchemy,这是我数据库上的 2 个表,
table name : student
- id (integer)
- student_name (varchar(20))
- edu_level_id (integer)
包含记录
id | student_name | edu_level_id
1 | John | 2
2 | George | 1
表:master_edu_level
* id (integer)
* name_level (varchar(50))
记录 :
id | name_level |
1 | high school
2 | Bachelor
3 | Master
如何显示记录:
id | student_name | education
1 | John | Bachelor
2 | George | high school
如果我这样解释 SQL:
select student.id, student.name,master_edu_level.name AS educatio FROM student
left join master_edu_Level ON master_edu_level.id = student.edu_level_id
我已经写了代码:
from app import db
from app import session
from sqlalchemy import Table, DateTime,Date, Text, text, Column, Integer, String, MetaData, ForeignKey, select, func
from sqlalchemy.ext.declarative import declarative_base
from marshmallow_jsonapi import Schema, fields
from marshmallow import validate
from marshmallow import ValidationError
from sqlalchemy.exc import SQLAlchemyError
from sqlalchemy.orm import relationship
class Student(db.Model):
__tablename__ = 'student'
id = db.Column(Integer, primary_key=True, index=True)
student_name = db.Column(String(20), nullable=False, index=True)
edu_level_id = db.Column(Integer)
class StudentSchema(Schema):
not_blank = validate.Length(min=1, error='Field cannot be blank')
id = fields.Integer(dump_only=True)
student_name = fields.String()
edu_level_id = fields.String()
class Meta:
type_ = 'student'
student_schema = StudentSchema()
class MasterEduLevel(db.Model):
__tablename__ = 'master_edu_level'
__table_args__ = {'extend_existing': True}
id = db.Column(Integer, primary_key=True, index=True)
name_level = db.Column(String(20), nullable=False, index=True)
class MasterEdulevelSchema(Schema):
not_blank = validate.Length(min=1, error='Field cannot be blank')
id = fields.Integer(dump_only=True)
name_level = fields.String()
class Meta:
type_ = 'master_edu_level'
schema = MasterEdulevelSchema()
如何在 python SQLAlchemy 上创建连接表 ORM?
谢谢