Method write_sql

python/ray/data/dataset.py:5194–5259

Write to a database that provides a `Python DB API2-compliant `_ connector. .. note:: This method writes data in parallel using the DB API2 ``executemany`` method. To learn more about this method, see `PEP 249 <

(
        self,
        sql: str,
        connection_factory: Callable[[], Connection],
        ray_remote_args: Optional[Dict[str, Any]] = None,
        concurrency: Optional[int] = None,
    )

    @ConsumptionAPI
    def write_sql(
        self,
        sql: str,
        connection_factory: Callable[[], Connection],
        ray_remote_args: Optional[Dict[str, Any]] = None,
        concurrency: Optional[int] = None,
    ) -> None:
        """Write to a database that provides a
        `Python DB API2-compliant <https://peps.python.org/pep-0249/>`_ connector.

        .. note::

            This method writes data in parallel using the DB API2 ``executemany``
            method. To learn more about this method, see
            `PEP 249 <https://peps.python.org/pep-0249/#executemany>`_.

        Examples:

            .. testcode::

                import sqlite3
                import ray

                connection = sqlite3.connect("example.db")
                connection.cursor().execute("CREATE TABLE movie(title, year, score)")
                dataset = ray.data.from_items([
                    {"title": "Monty Python and the Holy Grail", "year": 1975, "score": 8.2},
                    {"title": "And Now for Something Completely Different", "year": 1971, "score": 7.5}
                ])

                dataset.write_sql(
                    "INSERT INTO movie VALUES(?, ?, ?)", lambda: sqlite3.connect("example.db")
                )

                result = connection.cursor().execute("SELECT * FROM movie ORDER BY year")
                print(result.fetchall())

            .. testoutput::

                [('And Now for Something Completely Different', 1971, 7.5), ('Monty Python and the Holy Grail', 1975, 8.2)]

            .. testcode::
                :hide:

                import os
                os.remove("example.db")

        Arguments:
            sql: An ``INSERT INTO`` statement that specifies the table to write to. The
                number of parameters must match the number of columns in the table.
            connection_factory: A function that takes no arguments and returns a
                Python DB API2
                `Connection object <https://peps.python.org/pep-0249/#connection-objects>`_.
            ray_remote_args: Keyword arguments passed to :func:`ray.remote` in the
                write tasks.
            concurrency: The maximum number of Ray tasks to run concurrently. Set this
                to control number of tasks to run concurrently. This doesn&#x27;t change the
                total number of tasks run. By default, concurrency is dynamically