Empty Relation#
A empty
relation is a dummy relation, which can be used either for creating empty
data (but with a schema) during read operations or for throwing away records in
write operations.
Example#
relations:
empty:
kind: empty
schema:
kind: inline
fields:
- name: id
type: string
- name: amount
type: double
Fields#
kind
(mandatory) (string):empty
schema
(optional) (schema) (default: empty): Explicitly specifies the schema of the null relation.description
(optional) (string) (default: empty): A description of the relation. This is purely for informational purpose.partitions
(optional) (list:partition) (default: empty): Even though aempty
relation does not provide any physical storage, it still optionally provides virtual partition columns.
Output Modes#
A empty
relation supports all output modes, each of them simply discarding all records.