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+"""Illustrates the asyncio engine / connection interface.
+
+In this example, we have an async engine created by
+:func:`_engine.create_async_engine`. We then use it using await
+within a coroutine.
+
+"""
+
+
+import asyncio
+
+from sqlalchemy import Column
+from sqlalchemy import Integer
+from sqlalchemy import MetaData
+from sqlalchemy import String
+from sqlalchemy import Table
+from sqlalchemy.ext.asyncio import create_async_engine
+
+
+meta = MetaData()
+
+t1 = Table(
+ "t1", meta, Column("id", Integer, primary_key=True), Column("name", String)
+)
+
+
+async def async_main():
+ # engine is an instance of AsyncEngine
+ engine = create_async_engine(
+ "postgresql+asyncpg://scott:tiger@localhost/test", echo=True,
+ )
+
+ # conn is an instance of AsyncConnection
+ async with engine.begin() as conn:
+
+ # to support SQLAlchemy DDL methods as well as legacy functions, the
+ # AsyncConnection.run_sync() awaitable method will pass a "sync"
+ # version of the AsyncConnection object to any synchronous method,
+ # where synchronous IO calls will be transparently translated for
+ # await.
+ await conn.run_sync(meta.drop_all)
+ await conn.run_sync(meta.create_all)
+
+ # for normal statement execution, a traditional "await execute()"
+ # pattern is used.
+ await conn.execute(
+ t1.insert(), [{"name": "some name 1"}, {"name": "some name 2"}]
+ )
+
+ async with engine.connect() as conn:
+
+ # the default result object is the
+ # sqlalchemy.engine.Result object
+ result = await conn.execute(t1.select())
+
+ # the results are buffered so no await call is necessary
+ # for this case.
+ print(result.fetchall())
+
+ # for a streaming result that buffers only segments of the
+ # result at time, the AsyncConnection.stream() method is used.
+ # this returns a sqlalchemy.ext.asyncio.AsyncResult object.
+ async_result = await conn.stream(t1.select())
+
+ # this object supports async iteration and awaitable
+ # versions of methods like .all(), fetchmany(), etc.
+ async for row in async_result:
+ print(row)
+
+
+asyncio.run(async_main())