@Target(value=TYPE) @Retention(value=RUNTIME) public static @interface FunctionAnnotation.NonForwardedFieldsFirst
NOTE: The use of the NonForwardedFieldsFirst annotation is optional. If used correctly, it can help the Flink optimizer to generate more efficient execution plans. However if used incorrectly, it can cause invalid plan choices and the computation of wrong results! Since all not declared fields are considered to be forwarded, it is required that ALL non-forwarded fields of the first input are declared.
Non-forwarded fields are declared as a list of field expressions, e.g.,
declares that the second and fourth field of a Java tuple from the first input are modified and
all other fields of the first input are are not changed and remain on their position.
A NonForwardedFieldsFirst annotation can only be used on functions where the type of the first input and the output are identical.
Multiple non-forwarded fields can be annotated in one (
or separate Strings (
Please refer to the JavaDoc of
Function or Flink's documentation for
details on field expressions such as nested fields and wildcard.
public abstract String value
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