Sink data from RisingWave to Apache Doris

​

Prerequisites

• Ensure that RisingWave can access the network where the Doris backend and frontend are located. For more details, see Synchronize Data Through External Table.
• Ensure you have an upstream materialized view or source that you can sink data from. For more details, see CREATE SOURCE or CREATE MATERIALIZED VIEW.
• Ensure that for struct elements, the name and type are the same in Doris and RisingWave. If they are not the same, the values will be set to NULL or to default values. For more details on the struct data type, see Struct.

​

Syntax

CREATE SINK [ IF NOT EXISTS ] sink_name
[FROM sink_from | AS select_query]
WITH (
   connector='doris',
   connector_parameter = 'value', ...
);

​

Parameters

​

Examples

​

Create an append-only sink

To create an append-only sink, set type = 'append-only' in the CREATE SINK query.

CREATE SINK doris_sink FROM mv1
WITH (
    connector = 'doris',
    type = 'append-only',
    doris.url = 'http://fe:8030',
    doris.user = 'xxxx',
    doris.password = 'xxxx',
    doris.database = 'demo',
    doris.table='demo_bhv_table',
    force_append_only='true'
);

​

Create an upsert sink

To create an upsert sink, set type = 'upsert' in the CREATE SINK query. The Doris table must have a UNIQUE KEY when creating an upsert sink.

CREATE SINK doris_sink FROM mv1
WITH (
    connector = 'doris',
    type = 'upsert',
    doris.url = 'http://fe:8030',
    doris.user = 'xxxx',
    doris.password = 'xxxx',
    doris.database = 'demo',
    doris.table='demo_bhv_table',
    primary_key = 'user_id'
);

​

Data type mapping

The following table shows the corresponding data types between RisingWave and Doris that should be specified when creating a sink. For details on native RisingWave data types, see Overview of data types.

In regards to decimal types, RisingWave will round to the nearest decimal place to ensure that its precision matches that of Doris. Ensure that the length of decimal types being imported into Doris does not exceed Doris’s decimal length. Otherwise, it will fail to import.

If a decimal value is out of bounds or represents inf, -inf, or nan, RisingWave will insert null values.