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SELECT /*+ SHUFFLE_HASH('Orders', 'Customers') */ 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;

Note:

1. Table names in useSHUFFLE_hash HASH hint is required to avoid mistake hint propagation if there are multiple lookup joins.
2. The hint only provides a suggestion to the optimization, it is not an enforcer.

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      builder
        .hintStrategy("SHUFFLE_HASH",
            HintStrategy.builder(
                HintPredicates.and(HintPredicates.CORRELATE, isLookupJoin(), lookupJoinWithFixedTableName())))
        .build();

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LookupJoinRules would check whether FlinkLogicalJoin contain USESHUFFLE_HASH Hint. If yes, and the rules require the input must have hash distribution on join keys when converting FlinkLogicalJoin to LookupJoin.

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