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https://issues.apache.org/jira/browse/SPARK-23945?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Nicholas Chammas updated SPARK-23945:
-------------------------------------
Description:
In SQL you can filter rows based on the result of a subquery:
{code:java}
SELECT *
FROM table1
WHERE name NOT IN (
SELECT name
FROM table2
);{code}
In the Spark DataFrame API, the equivalent would probably look like this:
{code:java}
(table1
.where(
~col('name').isin(
table2.select('name')
)
)
){code}
However, .isin() currently [only accepts a local list of
values|http://spark.apache.org/docs/latest/api/python/pyspark.sql.html#pyspark.sql.Column.isin].
I imagine making this enhancement would happen as part of a larger effort to
support correlated subqueries in the DataFrame API.
Or perhaps there is no plan to support this style of query in the DataFrame
API, and queries like this should instead be written in a different way? How
would we write a query like the one I have above in the DataFrame API, without
needing to collect values locally for the NOT IN filter?
was:
In SQL you can filter rows based on the result of a subquery:
{code:java}
SELECT *
FROM table1
WHERE name NOT IN (
SELECT name
FROM table2
);{code}
In the Spark DataFrame API, the equivalent would probably look like this:
{code:java}
(table1
.where(
~col('name').isin(
table2.select('name')
)
)
){code}
However, .isin() currently [only accepts a local list of
values|http://spark.apache.org/docs/latest/api/python/pyspark.sql.html#pyspark.sql.Column.isin].
I imagine making this enhancement would happen as part of a larger effort to
support correlated subqueries in the DataFrame API.
Or perhaps there is no plan to support this style of query in the DataFrame
API, and queries like this should instead be written in a different way? How
would we write a query like the one I have above in the DataFrame API, without
needing to collect values locally for the NOT IN filter?
> Column.isin() should accept a single-column DataFrame as input
> --------------------------------------------------------------
>
> Key: SPARK-23945
> URL: https://issues.apache.org/jira/browse/SPARK-23945
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Affects Versions: 2.3.0
> Reporter: Nicholas Chammas
> Priority: Minor
>
> In SQL you can filter rows based on the result of a subquery:
> {code:java}
> SELECT *
> FROM table1
> WHERE name NOT IN (
> SELECT name
> FROM table2
> );{code}
> In the Spark DataFrame API, the equivalent would probably look like this:
> {code:java}
> (table1
> .where(
> ~col('name').isin(
> table2.select('name')
> )
> )
> ){code}
> However, .isin() currently [only accepts a local list of
> values|http://spark.apache.org/docs/latest/api/python/pyspark.sql.html#pyspark.sql.Column.isin].
> I imagine making this enhancement would happen as part of a larger effort to
> support correlated subqueries in the DataFrame API.
> Or perhaps there is no plan to support this style of query in the DataFrame
> API, and queries like this should instead be written in a different way? How
> would we write a query like the one I have above in the DataFrame API,
> without needing to collect values locally for the NOT IN filter?
>
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