JingsongLi opened a new pull request, #1770: URL: https://github.com/apache/incubator-paimon/pull/1770
<!-- Please specify the module before the PR name: [core] ... or [flink] ... --> ### Purpose <!-- Linking this pull request to the issue --> For Flink Lookup Join: ### Retry Lookup If the records of `Orders` (main table) join missing because the corresponding data of `customers` (lookup table) is not ready. You can consider using Flink's [Delayed Retry Strategy For Lookup](https://nightlies.apache.org/flink/flink-docs-master/docs/dev/table/sql/queries/hints/#3-enable-delayed-retry-strategy-for-lookup). Only for Flink 1.16+. ```sql -- enrich each order with customer information SELECT /*+ LOOKUP('table'='c', 'retry-predicate'='lookup_miss', 'retry-strategy'='fixed_delay', 'fixed-delay'='1s', 'max-attempts'='600') */ o.order_id, o.total, c.country, c.zip FROM Orders AS o JOIN customers FOR SYSTEM_TIME AS OF o.proc_time AS c ON o.customer_id = c.id; ``` ### Async Retry Lookup The problem with synchronous retry is that one record will block subsequent records, causing the entire job to be blocked. You can consider using async to avoid blocking. ```sql -- enrich each order with customer information SELECT /*+ LOOKUP('table'='c', 'retry-predicate'='lookup_miss', 'async'='true', 'output-mode'='allow_unordered', 'retry-strategy'='fixed_delay', 'fixed-delay'='1s', 'max-attempts'='600') */ o.order_id, o.total, c.country, c.zip FROM Orders AS o JOIN customers FOR SYSTEM_TIME AS OF o.proc_time AS c ON o.customer_id = c.id; ``` <!-- What is the purpose of the change --> ### Tests <!-- List UT and IT cases to verify this change --> ### API and Format <!-- Does this change affect API or storage format --> ### Documentation <!-- Does this change introduce a new feature --> -- 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]
