shrprasa commented on PR #40258: URL: https://github.com/apache/spark/pull/40258#issuecomment-1461288036
> Hm, how is it not ambiguous? When case insensitive, 'id' could mean one of two different columns It's not ambiguous because the when we are selecting using list of column names, both id and ID are getting value from same column 'id' in the source dataframe. val **df1** = sc.parallelize(List((1,2,3,4,5),(1,2,3,4,5))).toDF("**id"**,"col2","col3","col4", "col5") val op_cols_mixed_case = List(**"id"**,"col2","col3","col4", "col5", **"ID"**) val df3 = **df1**.select(op_cols_mixed_case.head, op_cols_mixed_case.tail: _*) df3.select("id").show() df3.explain() == Physical Plan == *(1) Project [**_1#6 AS id#17**, _2#7 AS col2#18, _3#8 AS col3#19, _4#9 AS col4#20, _5#10 AS col5#21, **_1#6 AS ID#17**] -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org