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BlackHole

docs/content/docs/connectors/table/blackhole.md

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BlackHole SQL Connector

{{< label "Sink: Bounded" >}} {{< label "Sink: UnBounded" >}}

The BlackHole connector allows for swallowing all input records. It is designed for:

  • high performance testing.
  • UDF to output, not substantive sink.

Just like /dev/null device on Unix-like operating systems.

The BlackHole connector is built-in.

How to create a BlackHole table

sql
CREATE TABLE blackhole_table (
  f0 INT,
  f1 INT,
  f2 STRING,
  f3 DOUBLE
) WITH (
  'connector' = 'blackhole'
);

Alternatively, it may be based on an existing schema using the [LIKE Clause]({{< ref "docs/sql/reference/ddl/create" >}}#create-table).

sql
CREATE TABLE blackhole_table WITH ('connector' = 'blackhole')
LIKE source_table (EXCLUDING ALL)

Connector Options

<table class="table table-bordered"> <thead> <tr> <th class="text-left" style="width: 25%">Option</th> <th class="text-center" style="width: 8%">Required</th> <th class="text-center" style="width: 7%">Default</th> <th class="text-center" style="width: 10%">Type</th> <th class="text-center" style="width: 50%">Description</th> </tr> </thead> <tbody> <tr> <td><h5>connector</h5></td> <td>required</td> <td style="word-wrap: break-word;">(none)</td> <td>String</td> <td>Specify what connector to use, here should be 'blackhole'.</td> </tr> </tbody> </table>