Github user dongjoon-hyun commented on the issue:
https://github.com/apache/spark/pull/14397
Hi, @hvanhovell . It seems not clearly documented, so I did some
comparisons.
First of all, I found that I did overlooked the behavior of the Hive
queries. Hive also uses CTE names first in the consecutive CTE queries like
other DBMS. It's natural.
```
with t as (select 10), s as (select * from t) select * from s;
```
For the self recursion, the approaches are different. Hive/Oracle raises
exceptions, PostgreSQL uses the base tables.
```
with t as (select 10 from t), s as (select * from t) select * from s;
```
The cross referencing case raises exceptions.
```
with t as (select 10 from s), s as (select * from t) select * from s;
```
To sum up, the general approach seems to
- use **forward-declared(not self)** base table or CTE name
- prevent the execution of cyclic queries by raising exceptions.
The root cause of previous Spark behavior is using `self` or
`backward-declared CTE` for table name resolutions. I will try to revise this
PR according to the above rules. Please comment about the above rule.
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