org.apache.flink.table.catalog

Interface CatalogView

All Superinterfaces:

CatalogBaseTable

All Known Implementing Classes:

ResolvedCatalogView

@PublicEvolving
public interface CatalogView
extends CatalogBaseTable

Represents the unresolved metadata of a view in a Catalog.

It contains all characteristics that can be expressed in a SQL CREATE VIEW statement. The framework will resolve instances of this interface to a ResolvedCatalogView before usage.

A catalog implementer can either use of(Schema, String, String, String, Map) for a basic implementation of this interface or create a custom class that allows passing catalog-specific objects (if necessary).

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.flink.table.catalog.CatalogBaseTable

CatalogBaseTable.TableKind

Method Summary

Modifier and Type	Method and Description
String	getExpandedQuery() Expanded text of the original view definition This is needed because the context such as current DB is lost after the session, in which view is defined, is gone.
String	getOriginalQuery() Original text of the view definition that also preserves the original formatting.
default CatalogBaseTable.TableKind	getTableKind() The kind of table this CatalogBaseTable describes.
static CatalogView	of(Schema schema, String comment, String originalQuery, String expandedQuery, Map<String,String> options) Creates a basic implementation of this interface.

Methods inherited from interface org.apache.flink.table.catalog.CatalogBaseTable

copy, getComment, getDescription, getDetailedDescription, getOptions, getSchema, getUnresolvedSchema

Method Detail

of

static CatalogView of(Schema schema,
                      @Nullable
                      String comment,
                      String originalQuery,
                      String expandedQuery,
                      Map<String,String> options)

Creates a basic implementation of this interface.

The signature is similar to a SQL CREATE VIEW statement.

Parameters:

schema - unresolved schema

comment - optional comment

originalQuery - original text of the view definition

expandedQuery - expanded text of the original view definition with materialized identifiers

options - options to configure the connector

getTableKind

default CatalogBaseTable.TableKind getTableKind()

Description copied from interface: CatalogBaseTable

The kind of table this CatalogBaseTable describes.

Specified by:

getTableKind in interface CatalogBaseTable

getOriginalQuery

String getOriginalQuery()

Original text of the view definition that also preserves the original formatting.

Returns:

the original string literal provided by the user.

getExpandedQuery

String getExpandedQuery()

Expanded text of the original view definition This is needed because the context such as current DB is lost after the session, in which view is defined, is gone. Expanded query text takes care of this, as an example.

For example, for a view that is defined in the context of "default" database with a query select * from test1, the expanded query text might become select `test1`.`name`, `test1`.`value` from `default`.`test1`, where table test1 resides in database "default" and has two columns ("name" and "value").

Returns:

the view definition in expanded text.