[
https://issues.apache.org/jira/browse/SPARK-33184?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17217001#comment-17217001
]
colin fang commented on SPARK-33184:
------------------------------------
I notice there is a quotation mark before `Project`. What does `!Project` mean?
> spark doesn't read data source column if it is used as an index to an array
> under a struct
> ------------------------------------------------------------------------------------------
>
> Key: SPARK-33184
> URL: https://issues.apache.org/jira/browse/SPARK-33184
> Project: Spark
> Issue Type: Improvement
> Components: Spark Core
> Affects Versions: 3.0.0
> Reporter: colin fang
> Priority: Minor
>
> {code:python}
> df = spark.createDataFrame([[1, [[1, 2]]]],
> schema='x:int,y:struct<a:array<int>>')
> df.write.mode('overwrite').parquet('test')
> {code}
> {code:python}
> # This causes an error "Caused by: java.lang.RuntimeException: Couldn't find
> x#720 in [y#721]"
> spark.read.parquet('test').select(F.expr('y.a[x]')).show()
> # Explain works fine, note it doesn't read x in ReadSchema
> spark.read.parquet('test').select(F.expr('y.a[x]')).explain()
> == Physical Plan ==
> *(1) !Project [y#713.a[x#712] AS y.a AS `a`[x]#717]
> +- FileScan parquet [y#713] Batched: false, DataFilters: [], Format: Parquet,
> Location: InMemoryFileIndex, PartitionFilters: [], PushedFilters: [],
> ReadSchema: struct<y:struct<a:array<int>>>
> {code}
> The code works well if I
> {code:python}
> # manually select the column it misses
> spark.read.parquet('test').select(F.expr('y.a[x]'), F.col('x')).show()
> # use element_at function
> spark.read.parquet('test').select(F.element_at('y.a', F.col('x') + 1)).show()
> {code}
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org
