SQLAlchemy ON DUPLICATE KEY UPDATE

Question

Is there an elegant way to do an INSERT ... ON DUPLICATE KEY UPDATE in SQLAlchemy? I mean something with a syntax similar to inserter.insert().execute(lis

Answer 1

My way

import typing
from datetime import datetime
from sqlalchemy.dialects import mysql

class MyRepository:

    def model(self):
        return MySqlAlchemyModel

    def upsert(self, data: typing.List[typing.Dict]):
        if not data:
            return
        model = self.model()
        if hasattr(model, 'created_at'):
            for item in data:
                item['created_at'] = datetime.now()

        stmt = mysql.insert(getattr(model, '__table__')).values(data)
        for_update = []
        for k, v in data[0].items():
            for_update.append(k)

        dup = {k: getattr(stmt.inserted, k) for k in for_update}
        stmt = stmt.on_duplicate_key_update(**dup)
        self.db.session.execute(stmt)
        self.db.session.commit()

Usage:

myrepo.upsert([
    {
        "field11": "value11",
        "field21": "value21",
        "field31": "value31",
    },
    {
        "field12": "value12",
        "field22": "value22",
        "field32": "value32",
    },
])