Hi,
I'm curious about the current status of the Recursive Queries feature
described on the Algebra documentation page:
https://calcite.apache.org/docs/algebra.html#recursive-queries
Those docs show some example recursive SQL that doesn't seem to work either
with the example/csv demo or with my downstream DBMS project. For example
this simplified SQL fails:
> WITH RECURSIVE aux AS (VALUES (1) UNION ALL VALUES (2)) SELECT * FROM aux;
Error: Error while executing SQL "WITH RECURSIVE aux AS (VALUES (1) UNION
ALL VALUES (2)) SELECT * FROM aux": parse failed: Incorrect syntax near the
keyword 'RECURSIVE' at line 1, column 6.
Was expecting one of:
<BRACKET_QUOTED_IDENTIFIER> ...
<QUOTED_IDENTIFIER> ...
<BACK_QUOTED_IDENTIFIER> ...
<BIG_QUERY_BACK_QUOTED_IDENTIFIER> ...
<HYPHENATED_IDENTIFIER> ...
<IDENTIFIER> ...
<UNICODE_QUOTED_IDENTIFIER> ... (state=,code=0)
But simply removing the RECURSIVE keyword allows the remaining SQL to
succeed:
> WITH aux AS (VALUES (1) UNION ALL VALUES (2)) SELECT * FROM aux;
+--------+
| EXPR$0 |
+--------+
| 1 |
| 2 |
+--------+
2 rows selected (0.043 seconds)
I see ticket CALCITE-129 from 2014 describing recursive WITH queries is
open, but reading through the email archives suggests it might be close to
completion.
https://issues.apache.org/jira/browse/CALCITE-129
What remains to be done to fully support recursive queries and how might I
be able to help?
Best,
Shawn Yarbrough
