Apache Spark reassigned SPARK-24288:

    Assignee: Apache Spark

> Enable preventing predicate pushdown
> ------------------------------------
>                 Key: SPARK-24288
>                 URL: https://issues.apache.org/jira/browse/SPARK-24288
>             Project: Spark
>          Issue Type: New Feature
>          Components: SQL
>    Affects Versions: 2.3.0
>            Reporter: Tomasz Gawęda
>            Assignee: Apache Spark
>            Priority: Major
>         Attachments: SPARK-24288.simple.patch
> Issue discussed on Mailing List: 
> [http://apache-spark-developers-list.1001551.n3.nabble.com/Preventing-predicate-pushdown-td23976.html]
> While working with JDBC datasource I saw that many "or" clauses with 
> non-equality operators causes huge performance degradation of SQL query 
> to database (DB2). For example: 
> val df = spark.read.format("jdbc").(other options to parallelize 
> load).load() 
> df.where(s"(date1 > $param1 and (date1 < $param2 or date1 is null) or x 
>  > 100)").show() // in real application whose predicates were pushed 
> many many lines below, many ANDs and ORs 
> If I use cache() before where, there is no predicate pushdown of this 
> "where" clause. However, in production system caching many sources is a 
> waste of memory (especially is pipeline is long and I must do cache many 
> times).There are also few more workarounds, but it would be great if Spark 
> will support preventing predicate pushdown by user.
> For example: df.withAnalysisBarrier().where(...) ?
> Note, that this should not be a global configuration option. If I read 2 
> DataFrames, df1 and df2, I would like to specify that df1 should not have 
> some predicates pushed down, but some may be, but df2 should have all 
> predicates pushed down, even if target query joins df1 and df2. As far as I 
> understand Spark optimizer, if we use functions like `withAnalysisBarrier` 
> and put AnalysisBarrier explicitly in logical plan, then predicates won't be 
> pushed down on this particular DataFrames and PP will be still possible on 
> the second one.

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