org.apache.spark.sql.jdbc

Class AggregatedDialect

Object

org.apache.spark.sql.jdbc.JdbcDialect

org.apache.spark.sql.jdbc.AggregatedDialect

All Implemented Interfaces:

java.io.Serializable

public class AggregatedDialect
extends JdbcDialect

AggregatedDialect can unify multiple dialects into one virtual Dialect. Dialects are tried in order, and the first dialect that does not return a neutral element will will.

param: dialects List of dialects.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
AggregatedDialect(scala.collection.immutable.List<JdbcDialect> dialects)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	canHandle(String url) Check if this dialect instance can handle a certain jdbc url.
scala.Option<DataType>	getCatalystType(int sqlType, String typeName, int size, MetadataBuilder md) Get the custom datatype mapping for the given jdbc meta information.
scala.Option<JdbcType>	getJDBCType(DataType dt) Retrieve the jdbc / sql type for a given datatype.

Methods inherited from class org.apache.spark.sql.jdbc.JdbcDialect

beforeFetch, getSchemaQuery, getTableExistsQuery, isCascadingTruncateTable, quoteIdentifier

Methods inherited from class Object

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

Constructor Detail

AggregatedDialect

public AggregatedDialect(scala.collection.immutable.List<JdbcDialect> dialects)

Method Detail

canHandle

public boolean canHandle(String url)

Description copied from class: JdbcDialect

Check if this dialect instance can handle a certain jdbc url.

Specified by:

canHandle in class JdbcDialect

Parameters:

url - the jdbc url.

Returns:

True if the dialect can be applied on the given jdbc url.

getCatalystType

public scala.Option<DataType> getCatalystType(int sqlType,
                                     String typeName,
                                     int size,
                                     MetadataBuilder md)

Description copied from class: JdbcDialect

Get the custom datatype mapping for the given jdbc meta information.

Overrides:

getCatalystType in class JdbcDialect

Parameters:

sqlType - The sql type (see java.sql.Types)

typeName - The sql type name (e.g. "BIGINT UNSIGNED")

size - The size of the type.

md - Result metadata associated with this type.

Returns:

The actual DataType (subclasses of DataType) or null if the default type mapping should be used.

getJDBCType

public scala.Option<JdbcType> getJDBCType(DataType dt)

Description copied from class: JdbcDialect

Retrieve the jdbc / sql type for a given datatype.

Overrides:

getJDBCType in class JdbcDialect

Parameters:

dt - The datatype (e.g. StringType)

Returns:

The new JdbcType if there is an override for this DataType