317brian commented on code in PR #15689: URL: https://github.com/apache/druid/pull/15689#discussion_r1480480808
########## docs/multi-stage-query/reference.md: ########## @@ -90,6 +93,93 @@ can precede the column list: `EXTEND (timestamp VARCHAR...)`. For more information, see [Read external data with EXTERN](concepts.md#read-external-data-with-extern). +#### `EXTERN` to export to a destination + +`EXTERN` can be used to specify a destination, where the data needs to be exported. +This variation of EXTERN requires one argument, the details of the destination as specified below. +This variation additionally requires an `AS` clause to specify the format of the exported rows. + +Only INSERT statements are supported with an `EXTERN` destination. +Only `CSV` format is supported at the moment. +Please note that partitioning (`PARTITIONED BY`) and clustering (`CLUSTERED BY`) is not currently supported with export statements. + +Export statements support the context parameter `rowsPerPage` for the number of rows in each exported file. The default value Review Comment: When you export data, use the `rowsPerPage` context parameter to control how many rows get exported. The default is 100,000. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
