CREATE TABLE

Use the CREATE TABLE command to create a new table. Tables consist of fixed columns and insertable rows. Rows can be added using the INSERT command. When creating a table, you can specify connector settings and data format.

info

If you choose to not persist the data from the source in RisingWave, you should use CREATE SOURCE.

Syntax

CREATE TABLE [ IF NOT EXISTS ] table_name (
    col_name data_type [ PRIMARY KEY ] [ AS generation_expression ],
    ...
    [ PRIMARY KEY (col_name, ... ) ]
    [ watermark_clause ]
)
[ APPEND ONLY ]
[ WITH (
    connector='connector_name',
    connector_parameter='value', ...)]
[FORMAT data_format ENCODE data_encode [ (
    message='message',
    schema.location='location', ...) ]
];

Notes

For tables with primary key constraints, if you insert a new data record with an existing key, the new record will overwrite the existing record.

Names and unquoted identifiers are case-insensitive. Therefore, you must double-quote any of these fields for them to be case-sensitive.

The syntax for creating a table with connector settings and the supported connectors are the same as for creating a source. See CREATE SOURCE for a full list of supported connectors and data formats.

To know when a data record is loaded to RisingWave, you can define a column that is generated based on the processing time (<column_name> timestamptz AS proctime()) when creating the table or source.

Parameters

Parameter	Description
table_name	The name of the table. If a schema name is given (for example, CREATE TABLE <schema>.<table> ...), then the table is created in the specified schema. Otherwise it is created in the current schema.
col_name	The name of a column.
data_type	The data type of a column. With the struct data type, you can create a nested table. Elements in a nested table need to be enclosed with angle brackets ("<>").
generation_expression	The expression for the generated column. For details about generated columns, see Generated columns.
watermark_clause	A clause that defines the watermark for a timestamp column. The syntax is WATERMARK FOR column_name as expr. For the watermark clause to be valid, the table must be an append-only table. That is, the APPEND ONLY option must be specified. This restriction only applies to a table. For details about watermarks, refer to Watermarks.
APPEND ONLY	When this option is specified, the table will be created as an append-only table. An append-only table cannot have primary keys. UPDATE and DELETE statements are not valid for append-only tables. Note that append-only tables are currently in Beta.
WITH clause	Specify the connector settings here if trying to store all the source data. See the Data ingestion page for the full list of supported source as well as links to specific connector pages detailing the syntax for each source.
FORMAT and ENCODE options	Specify the data format and the encoding format of the source data. To learn about the supported data formats, see Data formats.

Watermarks

RisingWave supports generating watermarks when creating an append-only streaming table. Watermarks are like markers or signals that track the progress of event time, allowing you to process events within their corresponding time windows. For more information on the syntax on how to create a watermark, see Watermarks.

Examples

The statement below creates a table that has three columns.

CREATE TABLE taxi_trips(
    id VARCHAR,
    distance DOUBLE PRECISION,
    city VARCHAR
);

The statement below creates a table that includes nested tables.

CREATE TABLE IF NOT EXISTS taxi_trips(
    id VARCHAR,
    distance DOUBLE PRECISION,
    duration DOUBLE PRECISION,
    fare STRUCT<
      initial_charge DOUBLE PRECISION, 
      subsequent_charge DOUBLE PRECISION, 
      surcharge DOUBLE PRECISION, 
      tolls DOUBLE PRECISION>);

The statement below creates a materialized source with a Kafka broker as the source.

CREATE TABLE IF NOT EXISTS source_abc (
   column1 varchar,
   column2 integer,
)
WITH (
   connector='kafka',
   topic='demo_topic',
   properties.bootstrap.server='172.10.1.1:9090,172.10.1.2:9090',
   scan.startup.mode='latest',
   scan.startup.timestamp_millis='140000000',
) FORMAT PLAIN ENCODE JSON;