Prompt: What does this code do?
class ExampleRow(NamedTuple): id: int name: str class JdbcOptions(PipelineOptions): @classmethod def _add_argparse_args(cls, parser): parser.add_argument( '--table_name', help='Table name' ) parser.add_argument( '--jdbc_url', help='JDBC URL' ) parser.add_argument( '--driver_class_name', help='Driver class name' ) parser.add_argument( '--username', help='Username' ) parser.add_argument( '--password', help='Password' ) options = JdbcOptions() coders.registry.register_coder(ExampleRow, coders.RowCoder) with beam.Pipeline(options=options) as p: output = (p | 'Read from JDBC' >> ReadFromJdbc( table_name=options.table_name, driver_class_name=options.driver_class_name, jdbc_url=options.jdbc_url, username=options.username, password=options.password ) | 'Log Data' >> Map(logging.info))
Response: This code reads data from an Oracle Java Database Connectivity (JDBC) enabled database using the ReadFromJdbc transform from the built-in JdbcIO connector.
class ExampleRow(NamedTuple): id: int name: str
This code defines a named tuple ExampleRow with two fields: id and name.
class JdbcOptions(PipelineOptions): @classmethod def _add_argparse_args(cls, parser): parser.add_argument( '--table_name', help='Table name' ) parser.add_argument( '--jdbc_url', help='JDBC URL' ) parser.add_argument( '--driver_class_name', help='Driver class name' ) parser.add_argument( '--username', help='Username' ) parser.add_argument( '--password', help='Password' ) options = JdbcOptions()
The JdbcOptions class defines the command-line arguments --table_name, --jdbc_url, --driver_class_name, --username, and --password, which specify the JDBC connection parameters. To parse command-line arguments, this code uses pipeline options.
coders.registry.register_coder(ExampleRow, coders.RowCoder)
This code registers a coder for the ExampleRow class. This is required for the ReadFromJdbc transform to read data from the table.
with beam.Pipeline(options=options) as p: output = (p | 'Read from JDBC' >> ReadFromJdbc( jdbc_url=options.jdbc_url, username=options.username, password=options.password, table_name=options.table_name, driver_class_name=options.driver_class_name ) | 'Log Data' >> Map(logging.info))
The Apache Beam pipeline uses the JdbcOptions class to set the path to the database and the ReadFromJdbc transform to read data from the database via JDBC.