Package org.apache.flink.table.data

Interface RowData

All Known Implementing Classes:
BinaryRowData, ColumnarRowData, GenericRowData, JoinedRowData, NestedRowData, ProjectedRowData
@PublicEvolving public interface RowData
Base interface for an internal data structure representing data of RowType and other (possibly nested) structured types such as StructuredType in the table ecosystem.

All top-level records that are travelling through Table API or SQL pipelines during runtime are instances of this interface. Each RowData contains a RowKind which represents the kind of change that a row describes in a changelog. The RowKind is just metadata information of row and thus not part of the table's schema, i.e., not a dedicated field.

Note: All fields of this data structure must be internal data structures.

The RowData interface has different implementations which are designed for different scenarios:

  • The binary-oriented implementation BinaryRowData is backed by references to MemorySegment instead of using Java objects to reduce the serialization/deserialization overhead.
  • The object-oriented implementation GenericRowData is backed by an array of Java Object which is easy to construct and efficient to update.

GenericRowData is intended for public use and has stable behavior. It is recommended to construct instances of RowData with this class if internal data structures are required.

The mappings from Flink's Table API and SQL data types to the internal data structures are listed in the following table: 

 +--------------------------------+-----------------------------------------+
 | SQL Data Types                 | Internal Data Structures                |
 +--------------------------------+-----------------------------------------+
 | BOOLEAN                        | boolean                                 |
 +--------------------------------+-----------------------------------------+
 | CHAR / VARCHAR / STRING        | StringData                      |
 +--------------------------------+-----------------------------------------+
 | BINARY / VARBINARY / BYTES     | byte[]                                  |
 +--------------------------------+-----------------------------------------+
 | DECIMAL                        | DecimalData                     |
 +--------------------------------+-----------------------------------------+
 | TINYINT                        | byte                                    |
 +--------------------------------+-----------------------------------------+
 | SMALLINT                       | short                                   |
 +--------------------------------+-----------------------------------------+
 | INT                            | int                                     |
 +--------------------------------+-----------------------------------------+
 | BIGINT                         | long                                    |
 +--------------------------------+-----------------------------------------+
 | FLOAT                          | float                                   |
 +--------------------------------+-----------------------------------------+
 | DOUBLE                         | double                                  |
 +--------------------------------+-----------------------------------------+
 | DATE                           | int (number of days since epoch)        |
 +--------------------------------+-----------------------------------------+
 | TIME                           | int (number of milliseconds of the day) |
 +--------------------------------+-----------------------------------------+
 | TIMESTAMP                      | TimestampData                   |
 +--------------------------------+-----------------------------------------+
 | TIMESTAMP WITH LOCAL TIME ZONE | TimestampData                   |
 +--------------------------------+-----------------------------------------+
 | INTERVAL YEAR TO MONTH         | int (number of months)                  |
 +--------------------------------+-----------------------------------------+
 | INTERVAL DAY TO MONTH          | long (number of milliseconds)           |
 +--------------------------------+-----------------------------------------+
 | ROW / structured types         | RowData                         |
 +--------------------------------+-----------------------------------------+
 | ARRAY                          | ArrayData                       |
 +--------------------------------+-----------------------------------------+
 | MAP / MULTISET                 | MapData                         |
 +--------------------------------+-----------------------------------------+
 | RAW                            | RawValueData                    |
 +--------------------------------+-----------------------------------------+

Nullability is always handled by the container data structure.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static interface 
    RowData.FieldGetter
    Accessor for getting the field of a row during runtime.

  • Method Summary

    Modifier and Type
    Method
    Description
    static RowData.FieldGetter
    createFieldGetter(LogicalType fieldType, int fieldPos)
    Creates an accessor for getting elements in an internal row data structure at the given position.
    int
    getArity()
    Returns the number of fields in this row.
    ArrayData
    getArray(int pos)
    Returns the array value at the given position.
    byte[]
    getBinary(int pos)
    Returns the binary value at the given position.
    boolean
    getBoolean(int pos)
    Returns the boolean value at the given position.
    byte
    getByte(int pos)
    Returns the byte value at the given position.
    DecimalData
    getDecimal(int pos, int precision, int scale)
    Returns the decimal value at the given position.
    double
    getDouble(int pos)
    Returns the double value at the given position.
    float
    getFloat(int pos)
    Returns the float value at the given position.
    int
    getInt(int pos)
    Returns the integer value at the given position.
    long
    getLong(int pos)
    Returns the long value at the given position.
    MapData
    getMap(int pos)
    Returns the map value at the given position.
    <T> RawValueData<T>
    getRawValue(int pos)
    Returns the raw value at the given position.
    RowData
    getRow(int pos, int numFields)
    Returns the row value at the given position.
    org.apache.flink.types.RowKind
    getRowKind()
    Returns the kind of change that this row describes in a changelog.
    short
    getShort(int pos)
    Returns the short value at the given position.
    StringData
    getString(int pos)
    Returns the string value at the given position.
    TimestampData
    getTimestamp(int pos, int precision)
    Returns the timestamp value at the given position.
    boolean
    isNullAt(int pos)
    Returns true if the field is null at the given position.
    void
    setRowKind(org.apache.flink.types.RowKind kind)
    Sets the kind of change that this row describes in a changelog.

  • Method Details

    • getArity

      int getArity()
      Returns the number of fields in this row.

      The number does not include RowKind. It is kept separately.

    • getRowKind

      org.apache.flink.types.RowKind getRowKind()
      Returns the kind of change that this row describes in a changelog.
      See Also:
      • RowKind

    • setRowKind

      void setRowKind(org.apache.flink.types.RowKind kind)
      Sets the kind of change that this row describes in a changelog.
      See Also:
      • RowKind

    • isNullAt

      boolean isNullAt(int pos)
      Returns true if the field is null at the given position.

    • getBoolean

      boolean getBoolean(int pos)
      Returns the boolean value at the given position.

    • getByte

      byte getByte(int pos)
      Returns the byte value at the given position.

    • getShort

      short getShort(int pos)
      Returns the short value at the given position.

    • getInt

      int getInt(int pos)
      Returns the integer value at the given position.

    • getLong

      long getLong(int pos)
      Returns the long value at the given position.

    • getFloat

      float getFloat(int pos)
      Returns the float value at the given position.

    • getDouble

      double getDouble(int pos)
      Returns the double value at the given position.

    • getString

      StringData getString(int pos)
      Returns the string value at the given position.

    • getDecimal

      DecimalData getDecimal(int pos, int precision, int scale)
      Returns the decimal value at the given position.

      The precision and scale are required to determine whether the decimal value was stored in a compact representation (see DecimalData).

    • getTimestamp

      TimestampData getTimestamp(int pos, int precision)
      Returns the timestamp value at the given position.

      The precision is required to determine whether the timestamp value was stored in a compact representation (see TimestampData).

    • getRawValue

      <T> RawValueData<T> getRawValue(int pos)
      Returns the raw value at the given position.

    • getBinary

      byte[] getBinary(int pos)
      Returns the binary value at the given position.

    • getArray

      ArrayData getArray(int pos)
      Returns the array value at the given position.

    • getMap

      MapData getMap(int pos)
      Returns the map value at the given position.

    • getRow

      RowData getRow(int pos, int numFields)
      Returns the row value at the given position.

      The number of fields is required to correctly extract the row.

    • createFieldGetter

      static RowData.FieldGetter createFieldGetter(LogicalType fieldType, int fieldPos)
      Creates an accessor for getting elements in an internal row data structure at the given position.
      Parameters:
      fieldType - the element type of the row
      fieldPos - the element position of the row