发生冲突时，使用sqlalchemy更新jsonb列？

Question

如果与现有表不同，我想更新“ raw_data”表中的“ info”列。

其中“ info”是JSONB数据类型。

例如，如果“信息”数据存在，则不要执行，否则进行更新。

我可以使用psycopg2做到这一点：

cursor = connection.cursor()

postgres_insert_query = 
"""
INSERT INTO raw_data ("timestamp", imie, info) 
VALUES (timestamp '2019-07-22 00:00:00', '1234', '{"x": 1, "someData": "on"}')
ON CONFLICT ("timestamp")
DO UPDATE 
  SET info = EXCLUDED.info 
WHERE raw_data.info IS DISTINCT FROM EXCLUDED.info;"""

record_to_insert = (int(timestamp), int(imei), json_file)
cursor.execute(postgres_insert_query, record_to_insert)
connection.commit()

使用此样本表：

create table raw_data ("timestamp" timestamp primary key, imie text, info jsonb);

然后，您可以运行以下命令：

INSERT INTO raw_data ("timestamp", imie, info) 
VALUES (timestamp '2019-07-22 00:00:00', '1234', '{"x": 1, "someData": "on"}')
ON CONFLICT ("timestamp")
DO UPDATE 
  SET info = EXCLUDED.info 
WHERE raw_data.info IS DISTINCT FROM EXCLUDED.info;

上面代码的在线示例： https : //rextester.com/IOYXB82745

[主要挑战]：我想知道是否可以做类似的事情，但是使用sqlalchemy：

这是我目前所拥有的：

from sqlalchemy import create_engine  
from sqlalchemy import Column, String  
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.dialects.postgresql import INET, JSONB, SMALLINT, BIGINT
from sqlalchemy.orm import sessionmaker

db_string = "postgres://admin:donotusethispassword@aws-us-east-1-portal.19.dblayer.com:15813/compose"

db = create_engine(db_string)  
base = declarative_base()

class TelData(base):
    __tablename__ = 'raw_data'
    timestamp = Column(BIGINT, primary_key=True)
    imie = Column(BIGINT)
    info = Column(JSONB)
Session = sessionmaker(db)  
session = Session()

base.metadata.create_all(db)