CREATE SINK

Use the CREATE SINK command to create a sink. A sink is an external target where you can send data processed in RisingWave. You can create a sink from a table or a materialized view.

If your goal is to create an append-only sink, you can use the emit-on-window-close policy when creating the materialized view that you want to sink data from. For details about the policy, see Emit on window close.

Syntax

CREATE SINK [ IF NOT EXISTS ] sink_name
[FROM sink_from | AS select_query]
WITH (
   connector = 'connector_name',
   connector_parameter = 'value',
   [ snapshot = 'true' | 'false' ],
   [ cloud.serverless_backfill_enabled = true | false ],...
)
[ FORMAT data_format ENCODE data_encode [ (
    format_parameter = 'value'
) ] ];

Parameters

Parameter	Description
sink_name	The name of the sink.
col_name	The name of the column.
sink_from	Specify the upstream for the sink: a source, table, or materialized view. For CDC data, the upstream must be a table.
select_query	Specify the data to be output to the sink.
snapshot	Optional. Set this parameter to false to skip backfilling historical data and transmit only incremental changes. This option is only applicable when using the CREATE SINK FROM syntax, not CREATE SINK AS. The default value is true. To replace an existing sink without historical backfill, use REPLACE SINK.
cloud.serverless_backfill_enabled	Optional. Runs the initial backfill on dedicated serverless backfiller nodes for this statement. Supported only in RisingWave Cloud. Enable serverless backfilling in the Cloud console first. Serverless backfilling is not supported for databases in non-default resource groups.
force_compaction	Optional. When set to true, forces buffering and compaction even when the stream key matches the sink primary key exactly. This reduces the number of output messages by emitting at most one update per key within each barrier interval. The default value is false. For more information, see Force compaction.
WITH clause	Specify the connector settings here if trying to store all the sink data. See Supported sinks for the full list of supported sink as well as links to specific connector pages detailing the syntax for each sink.
FORMAT and ENCODE options	Optional. Specify the data format and the encoding format of the sink data. It is only used for Kafka, Kinesis, Pulsar, and Redis sinks.

Please distinguish between the parameters set in the FORMAT and ENCODE options and those set in the WITH clause. Ensure that you place them correctly and avoid any misuse.

Backfill and isolation

When creating a sink, RisingWave will backfill historical data from the upstream source, table, or materialized view (unless snapshot=false is specified). Snapshot backfill is enabled by default to improve isolation between the backfill phase and streaming phase. This helps prevent resource contention between backfilling historical data and processing new streaming data. To disable it if needed, set SET streaming_use_snapshot_backfill=false; before creating the sink. For more details, see View and configure runtime parameters.

In RisingWave Cloud, you can offload sink backfill to dedicated serverless backfiller nodes. Enable it for the current session with SET enable_serverless_backfill = true; or for one statement with WITH (cloud.serverless_backfill_enabled = true). For setup and limitations, see Serverless backfilling.

Supported sinks

Click a sink name to see the SQL syntax, options, and sample statement of sinking data from RisingWave to the sink.

• Apache Doris
• Apache Iceberg
• AWS Kinesis
• Cassandra or ScyllaDB
• ClickHouse
• CockroachDB
• Delta Lake
• Elasticsearch
• Google BigQuery
• Kafka (Supports versions 3.1.0 or later)
• MySQL (Supports versions 5.7 and 8.0.x)
• NATS
• PostgreSQL
• Pulsar
• Redis
• StarRocks
• TiDB
• Turbopuffer

See also

Overview of data delivery

DROP SINK

Remove a sink

REPLACE SINK

Replace an existing sink

SHOW CREATE SINK

Show the SQL statement used to create a sink

CREATE SINK INTO

Create a sink into RisingWave’s table

Timestamptz values are stored in UTC.

When sinking downstream, the representation of timestamptz is configurable. By default, it is in the format 2023-11-11T18:30:09.453000Z.