org.apache.beam.sdk.extensions.sql.impl

Class JdbcDriver

java.lang.Object

org.apache.calcite.avatica.UnregisteredDriver

org.apache.calcite.jdbc.Driver

org.apache.beam.sdk.extensions.sql.impl.JdbcDriver

All Implemented Interfaces:

java.sql.Driver

@AutoService(value=java.sql.Driver.class)
public class JdbcDriver
extends org.apache.calcite.jdbc.Driver

Calcite JDBC driver with Beam defaults.

Connection URLs have this form:

jdbc:beam:param1=value1;param2=value2;param3=value3

The querystring-style parameters are parsed as PipelineOptions.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.calcite.avatica.UnregisteredDriver

org.apache.calcite.avatica.UnregisteredDriver.JdbcVersion

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	CONNECT_STRING_PREFIX
static JdbcDriver	INSTANCE

Fields inherited from class org.apache.calcite.avatica.UnregisteredDriver

factory, handler

Constructor Summary

Constructors

Constructor and Description
JdbcDriver()

Method Summary

Modifier and Type	Method and Description
java.sql.Connection	connect(java.lang.String url, java.util.Properties originalConnectionProperties) Configures Beam-specific options and opens a JDBC connection to Calcite.
static JdbcConnection	connect(TableProvider tableProvider) Connects to the driver using standard connect(String, Properties) call, but overrides the initial schema factory.
protected java.lang.String	getConnectStringPrefix()

Methods inherited from class org.apache.calcite.jdbc.Driver

createDriverVersion, createHandler, createMeta, createPrepareFactory, getConnectionProperties, getFactoryClassName

Methods inherited from class org.apache.calcite.avatica.UnregisteredDriver

acceptsURL, createFactory, getDriverVersion, getMajorVersion, getMinorVersion, getParentLogger, getPropertyInfo, instantiateFactory, jdbcCompliant, register

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

INSTANCE

public static final JdbcDriver INSTANCE

CONNECT_STRING_PREFIX

public static final java.lang.String CONNECT_STRING_PREFIX

See Also:

Constant Field Values

Constructor Detail

JdbcDriver

public JdbcDriver()

Method Detail

getConnectStringPrefix

protected java.lang.String getConnectStringPrefix()

Overrides:

getConnectStringPrefix in class org.apache.calcite.jdbc.Driver

connect

public java.sql.Connection connect(java.lang.String url,
                                   java.util.Properties originalConnectionProperties)
                            throws java.sql.SQLException

Configures Beam-specific options and opens a JDBC connection to Calcite.

If originalConnectionProperties doesn't have the Beam-specific properties, populates them with defaults (e.g. sets the default schema name to "beam").

Returns null if url doesn't begin with CONNECT_STRING_PREFIX. This seems to be how JDBC decides whether a driver can handle a request. It tries to connect to it, and if the result is null it picks another driver.

Returns an instance of JdbcConnection which is a Beam wrapper around CalciteConnection.

Specified by:

connect in interface java.sql.Driver

Overrides:

connect in class org.apache.calcite.avatica.UnregisteredDriver

Throws:

java.sql.SQLException

connect

public static JdbcConnection connect(TableProvider tableProvider)

Connects to the driver using standard connect(String, Properties) call, but overrides the initial schema factory. Default factory would load up all table providers. The one specified here doesn't load any providers. We then override the top-level schema with the tableProvider.

This is called in tests and BeamSqlEnv, core part of SqlTransform. CLI uses standard JDBC driver registry, and goes through connect(String, Properties) instead, not this path. The CLI ends up using the schema factory that populates the default schema with all table providers it can find. See BeamCalciteSchemaFactory.