使用 SQLAlchemy Core 批量插入列表值

Question

I'd like to bulk insert a list of strings into a MySQL Database with SQLAlchemy Core.

engine = create_engine("mysql+mysqlconnector://...")
meta = MetaData()
meta.bind = engine

My table layout looks like this - together with two currently unused columns (irrelevant1/2):

MyTabe = Table('MyTable', meta,
Column('id', Integer, primary_key=True), 
Column('color', Text),
Column('irrelevant1', Text)
Column('irrelevant2', Text))

Unfortunately the following does not work - it inserts an empty row. What's the right way to do this?

MyTable.insert().execute(['blue', 'red', 'green'])

Answer 1

Here's one way to do it:

MyTable.__table__.insert().execute([{'color': 'blue'}, 
                                    {'color': 'red'}, 
                                    {'color': 'green'}])

Or, using connection.execute() :

conn.execute(MyTable.insert(), [{'color': 'blue'}, 
                                {'color': 'red'}, 
                                {'color': 'green'}])

You can easily make a list of dicts from the list you have:

[{'color': value} for value in colors]

Answer 2

Another way to do it:

from sqlalchemy import MetaData, Table, create_engine

engine = create_engine("mysql+mysqlconnector://....")
metadata = MetaData()
metadata.reflect(engine, only=['MyTable'])
table = Table('MyTable', meta, autoload=True, autoload_with=engine)

engine.execute(table.insert(), [{'color': 'blue'}, 
                            {'color': 'red'}, 
                            {'color': 'green'}])