dilipbiswal edited a comment on issue #24150: [SPARK-27209][SQL] Split parsing 
of SELECT and INSERT into two top-level rules in the grammar file.
URL: https://github.com/apache/spark/pull/24150#issuecomment-475666231
 
 
   @cloud-fan @viirya 
   **Update**
   Basically i was trying to understand and answer the question both of you 
have raised which is
   why make insertInto optional if we are splitting insert and select ? 
   
   The only test that fails after making `insertInto` mandatory in 
`multiInsertQueryBody` is PlanParserSuite:"test("multi select query")". 
Currently we allow multi insert and multi select queries like following : 
   ```
   FROM T1
   INSERT INTO T2 SELECT WHERE <condition>
   INSERT INTO T3 SELECT WHERE <another_condition>
   ```
   AND
   ```
   FROM T1
   SELECT C1 WHERE <condition>
   SELECT C1 WHERE <another_condition>
   ```
   Given **only the planParseSuite is affected**, my thinking is , this multi 
select support is NOT really something we were designing to support. What we 
wanted to support is a `insert into.. select from`. Currently we plan the 
multi-select queries by simply unioning each branch. My question is , is this 
something we should continue to support ? Since there are better ways to 
support union queries, i am wondering why would users ever want to use this way 
? WDYT ?
   

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