Package org.apache.flink.table.catalog

Class ResolvedSchema

java.lang.Object

org.apache.flink.table.catalog.ResolvedSchema

@PublicEvolving
public final class ResolvedSchema
extends Object

Schema of a table or view consisting of columns, constraints, and watermark specifications.

This class is the result of resolving a Schema into a final validated representation.

• Data types and functions have been expanded to fully qualified identifiers.
• Time attributes are represented in the column's data type.
• Expressions have been translated to ResolvedExpression.
• AbstractDataTypes have been translated to DataType.

This class should not be passed into a connector. It is therefore also not serializable. Instead, the toPhysicalRowDataType() can be passed around where necessary.

Constructor Summary

Constructors

Constructor	Description
ResolvedSchema(List<Column> columns, List<WatermarkSpec> watermarkSpecs, UniqueConstraint primaryKey)

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object o)
Optional<Column>	getColumn(int columnIndex)	Returns the Column instance for the given column index.
Optional<Column>	getColumn(String columnName)	Returns the Column instance for the given column name.
int	getColumnCount()	Returns the number of Columns of this schema.
List<DataType>	getColumnDataTypes()	Returns all column data types.
List<String>	getColumnNames()	Returns all column names.
List<Column>	getColumns()	Returns all Columns of this schema.
Optional<UniqueConstraint>	getPrimaryKey()	Returns the primary key if it has been defined.
int[]	getPrimaryKeyIndexes()	Returns the primary key indexes, if any, otherwise returns an empty array.
List<WatermarkSpec>	getWatermarkSpecs()	Returns a list of watermark specifications each consisting of a rowtime attribute and watermark strategy expression.
int	hashCode()
static ResolvedSchema	of(List<Column> columns)	Shortcut for a resolved schema of only columns.
static ResolvedSchema	of(Column... columns)	Shortcut for a resolved schema of only columns.
static ResolvedSchema	physical(String[] columnNames, DataType[] columnDataTypes)	Shortcut for a resolved schema of only physical columns.
static ResolvedSchema	physical(List<String> columnNames, List<DataType> columnDataTypes)	Shortcut for a resolved schema of only physical columns.
DataType	toPhysicalRowDataType()	Converts all physical columns of this schema into a (possibly nested) row data type.
DataType	toSinkRowDataType()	Converts all persisted columns of this schema into a (possibly nested) row data type.
DataType	toSourceRowDataType()	Converts all columns of this schema into a (possibly nested) row data type.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

ResolvedSchema

public ResolvedSchema(List<Column> columns,
 List<WatermarkSpec> watermarkSpecs,
 @Nullable
 UniqueConstraint primaryKey)

Method Details

of

public static ResolvedSchema of(List<Column> columns)

Shortcut for a resolved schema of only columns.

of

public static ResolvedSchema of(Column... columns)

Shortcut for a resolved schema of only columns.

physical

public static ResolvedSchema physical(List<String> columnNames,
 List<DataType> columnDataTypes)

Shortcut for a resolved schema of only physical columns.

physical

public static ResolvedSchema physical(String[] columnNames,
 DataType[] columnDataTypes)

Shortcut for a resolved schema of only physical columns.

getColumnCount

public int getColumnCount()

Returns the number of Columns of this schema.

getColumns

public List<Column> getColumns()

Returns all Columns of this schema.

getColumnNames

public List<String> getColumnNames()

Returns all column names. It does not distinguish between different kinds of columns.

getColumnDataTypes

public List<DataType> getColumnDataTypes()

Returns all column data types. It does not distinguish between different kinds of columns.

getColumn

public Optional<Column> getColumn(int columnIndex)

Returns the Column instance for the given column index.

Parameters:

columnIndex - the index of the column

getColumn

public Optional<Column> getColumn(String columnName)

Returns the Column instance for the given column name.

Parameters:

columnName - the name of the column

getWatermarkSpecs

public List<WatermarkSpec> getWatermarkSpecs()

Returns a list of watermark specifications each consisting of a rowtime attribute and watermark strategy expression.

Note: Currently, there is at most one WatermarkSpec in the list, because we don't support multiple watermark definitions yet.

getPrimaryKey

public Optional<UniqueConstraint> getPrimaryKey()

Returns the primary key if it has been defined.

getPrimaryKeyIndexes

public int[] getPrimaryKeyIndexes()

Returns the primary key indexes, if any, otherwise returns an empty array.

toSourceRowDataType

public DataType toSourceRowDataType()

Converts all columns of this schema into a (possibly nested) row data type.

This method returns the source-to-query schema.

Note: The returned row data type contains physical, computed, and metadata columns. Be careful when using this method in a table source or table sink. In many cases, toPhysicalRowDataType() might be more appropriate.

See Also:

• DataTypes.ROW(DataTypes.Field...)
• toPhysicalRowDataType()
• toSinkRowDataType()

toPhysicalRowDataType

public DataType toPhysicalRowDataType()

Converts all physical columns of this schema into a (possibly nested) row data type.

Note: The returned row data type contains only physical columns. It does not include computed or metadata columns.

See Also:

• DataTypes.ROW(DataTypes.Field...)
• toSourceRowDataType()
• toSinkRowDataType()

toSinkRowDataType

public DataType toSinkRowDataType()

Converts all persisted columns of this schema into a (possibly nested) row data type.

This method returns the query-to-sink schema.

Note: Computed columns and virtual columns are excluded in the returned row data type. The data type contains the columns of toPhysicalRowDataType() plus persisted metadata columns.

See Also:

• DataTypes.ROW(DataTypes.Field...)
• toSourceRowDataType()
• toPhysicalRowDataType()

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object