@PublicEvolving public abstract class Column extends Object
ResolvedSchema
.
A table column describes either a Column.PhysicalColumn
, Column.ComputedColumn
, or Column.MetadataColumn
.
Every column is fully resolved. The enclosed DataType
indicates whether the column is
a time attribute and thus might differ from the original data type.
Modifier and Type | Class and Description |
---|---|
static class |
Column.ComputedColumn
Representation of a computed column.
|
static class |
Column.MetadataColumn
Representation of a metadata column.
|
static class |
Column.PhysicalColumn
Representation of a physical column.
|
Modifier and Type | Field and Description |
---|---|
protected DataType |
dataType |
protected String |
name |
Modifier and Type | Method and Description |
---|---|
String |
asSummaryString()
Returns a string that summarizes this column for printing to a console.
|
static Column.ComputedColumn |
computed(String name,
ResolvedExpression expression)
Creates a computed column that is computed from the given
ResolvedExpression . |
abstract Column |
copy(DataType newType)
Returns a copy of the column with a replaced
DataType . |
boolean |
equals(Object o) |
abstract Optional<String> |
explainExtras()
Returns an explanation of specific column extras next to name and type.
|
DataType |
getDataType()
Returns the data type of this column.
|
String |
getName()
Returns the name of this column.
|
int |
hashCode() |
abstract boolean |
isPersisted()
Returns whether the given column is persisted in a sink operation.
|
abstract boolean |
isPhysical()
Returns whether the given column is a physical column of a table; neither computed nor
metadata.
|
static Column.MetadataColumn |
metadata(String name,
DataType dataType,
String metadataKey,
boolean isVirtual)
Creates a metadata column from metadata of the given column name or from metadata of the
given key (if not null).
|
static Column.PhysicalColumn |
physical(String name,
DataType dataType)
Creates a regular table column that represents physical data.
|
String |
toString() |
public static Column.PhysicalColumn physical(String name, DataType dataType)
public static Column.ComputedColumn computed(String name, ResolvedExpression expression)
ResolvedExpression
.public static Column.MetadataColumn metadata(String name, DataType dataType, @Nullable String metadataKey, boolean isVirtual)
Allows to specify whether the column is virtual or not.
public abstract boolean isPhysical()
public abstract boolean isPersisted()
public DataType getDataType()
public String getName()
public String asSummaryString()
public abstract Optional<String> explainExtras()
public abstract Column copy(DataType newType)
DataType
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