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https://issues.apache.org/jira/browse/CALCITE-5971?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17769890#comment-17769890
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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



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