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LakeShen commented on CALCITE-5971: ----------------------------------- Hi [~zhoujira86] ,it's ok for you to contribute to flink. > Add the RelRule to rewrite the bernoulli sample as Filter > ---------------------------------------------------------- > > Key: CALCITE-5971 > URL: https://issues.apache.org/jira/browse/CALCITE-5971 > Project: Calcite > Issue Type: New Feature > Components: core > Reporter: LakeShen > Assignee: LakeShen > Priority: Major > Labels: pull-request-available > Fix For: 1.36.0 > > > For the following SQL: > {code:java} > select deptno from "scott".dept tablesample bernoulli(50); {code} > We could rewrite it to: > {code:java} > select deptno from "scott".dept where rand() < 0.5; {code} > The sql : > {code:java} > select deptno from "scott".dept tablesample bernoulli(50) REPEATABLE(10); > {code} > We could rewrite it to: > {code:java} > select deptno from "scott".dept where rand(10) < 0.5; {code} > This rule only rewrite the tablesample bernoulli,and this rule is like > presto/trino's > [ImplementBernoulliSampleAsFilter|https://github.com/prestodb/presto/blob/6eef062bdd3777936fa29127e728edde86a681d4/presto-main/src/main/java/com/facebook/presto/sql/planner/iterative/rule/ImplementBernoulliSampleAsFilter.java#L47C1-L48C35] > rule -- This message was sent by Atlassian Jira (v8.20.10#820010)