LOL First one
spark-sql> select 1 as `data.group` from abc group by data.group; 1 Time taken: 0.198 seconds, Fetched 1 row(s) means that are assigning alias data.group to select and you are using that alias -> data.group in your group by statement This is equivalent to spark-sql> select 1 as `data.group` from abc group by 1; 1 With regard to your second sql select 1 as *`data.group`* from tbl group by `*data.group`;* *will throw an error * *spark-sql> select 1 as `data.group` from abc group by `data.group`;* *Error in query: cannot resolve '`data.group`' given input columns: [spark_catalog.elayer.abc.keyword, spark_catalog.elayer.abc.occurence]; line 1 pos 43;* *'Aggregate ['`data.group`], [1 AS data.group#225]* *+- SubqueryAlias spark_catalog.elayer.abc* * +- HiveTableRelation [`elayer`.`abc`, org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe, Data Cols: [keyword#226, occurence#227L], Partition Cols: []]* `data.group` with quotes is neither the name of the column or its alias *HTH* view my Linkedin profile <https://www.linkedin.com/in/mich-talebzadeh-ph-d-5205b2/> https://en.everybodywiki.com/Mich_Talebzadeh *Disclaimer:* Use it at your own risk. Any and all responsibility for any loss, damage or destruction of data or any other property which may arise from relying on this email's technical content is explicitly disclaimed. The author will in no case be liable for any monetary damages arising from such loss, damage or destruction. On Fri, 27 Jan 2023 at 23:36, Kohki Nishio <tarop...@gmail.com> wrote: > this SQL works > > select 1 as *`data.group`* from tbl group by *data.group* > > > Since there's no such field as *data,* I thought the SQL has to look like > this > > select 1 as *`data.group`* from tbl group by `*data.group`* > > > But that gives and error (cannot resolve '`data.group`') ... I'm no > expert in SQL, but feel like it's a strange behavior... does anybody have a > good explanation for it ? > > Thanks > > -- > Kohki Nishio >
