This topic provides the DDL syntax that is used to create a print result table and describes the parameters in the WITH clause. You can use a print result table to test a streaming job or debug a production job, and check whether the data result meets your business requirements.

Limits

Only Flink that uses Ververica Runtime (VVR) 2.1.5 or later supports print connectors.

Precautions

  • If you want to view the output data of a print result table, you must set the log level to INFO. If you do not set the log level to INFO, you cannot view the output data.
  • For security reasons, the system limits the number of data records that can be displayed in the taskmanager.log file. If you want to check for dirty data or specific data, we recommend that you specify conditions in the WHERE clause to perform the print operation. The print operation ensures that the required data can be checked even if 2,000 data records are displayed.

DDL syntax

CREATE TABLE print_table (
  a INT,
  b varchar
) WITH (
  'connector'='print',
  'logger'='true'
);

Parameters in the WITH clause

Parameter Description Required Remarks
connector The type of the result table. Yes Set the value to print.
logger Specifies whether to display the data result in the console. No Valid values:
  • false: The data result is not displayed in the console. This is the default value.
  • true: The data result is displayed in the console.
print-identifier The identifier of the data result. No The log information is retrieved by using the identifier of the data result.
sink.parallelism The parallelism of the result table. No By default, the value is the same as the parallelism of the upstream storage.

FAQ

How do I view print data results in the console of fully managed Flink?