Package org.apache.spark.sql.connector.catalog

Class DelegatingTable

Object

org.apache.spark.sql.connector.catalog.DelegatingTable

All Implemented Interfaces:

Relation, Table

@Evolving
public class DelegatingTable
extends Object
implements Table

A concrete Table that adapts a TableInfo -- it contains only table metadata and defers read/write to Spark, which resolves the table provider into a data source at read time.

Catalogs build the metadata via TableInfo.Builder and return a DelegatingTable from TableCatalog.loadTable(Identifier) (or RelationCatalog.loadRelation(org.apache.spark.sql.connector.catalog.Identifier) for a data-source table) when they want Spark to handle the underlying source. A catalog that has its own Table object returns that instead. Views are never represented as a DelegatingTable: a view is a View, which is itself a Relation.

Since:

4.2.0

Constructor Summary

Constructors

Constructor	Description
DelegatingTable(TableInfo info, String name)

Method Summary

Modifier and Type	Method	Description
Set<TableCapability>	capabilities()	Returns the set of capabilities for this table.
Column[]	columns()	Returns the columns of this table.
Constraint[]	constraints()	Returns the constraints for this table.
TableInfo	getTableInfo()
String	name()	A name to identify this table.
Transform[]	partitioning()	Returns the physical partitioning of this table.
Map<String,String>	properties()	Returns the string map of table properties.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.spark.sql.connector.catalog.Table

id, schema, version

Constructor Details

DelegatingTable

public DelegatingTable(TableInfo info,
 String name)

Parameters:

info - the table metadata to delegate to.

name - human-readable name for this table, returned by name() and surfaced in places that read it (e.g. BatchScan plan-tree labels and partition-management error messages). DESCRIBE TABLE EXTENDED does not read this field; it emits the resolved identifier as structured Catalog / Namespace / Table rows. Catalogs returning a DelegatingTable from TableCatalog.loadTable(org.apache.spark.sql.connector.catalog.Identifier) or RelationCatalog.loadRelation(org.apache.spark.sql.connector.catalog.Identifier) should typically pass ident.toString(), matching the quoted multi-part form used elsewhere for v2 identifiers.

Method Details

getTableInfo

public TableInfo getTableInfo()

columns

public Column[] columns()

Description copied from interface: Table

Returns the columns of this table. If the table is not readable and doesn't have a schema, an empty array can be returned here.

Specified by:

columns in interface Relation

Specified by:

columns in interface Table

properties

public Map<String,String> properties()

Description copied from interface: Table

Returns the string map of table properties.

Specified by:

properties in interface Relation

Specified by:

properties in interface Table

partitioning

public Transform[] partitioning()

Description copied from interface: Table

Returns the physical partitioning of this table.

Specified by:

partitioning in interface Table

constraints

public Constraint[] constraints()

Description copied from interface: Table

Returns the constraints for this table.

Specified by:

constraints in interface Table

name

public String name()

Description copied from interface: Table

A name to identify this table. Implementations should provide a meaningful name, like the database and table name from catalog, or the location of files for this table.

Specified by:

name in interface Table

capabilities

public Set<TableCapability> capabilities()

Description copied from interface: Table

Returns the set of capabilities for this table.

Specified by:

capabilities in interface Table