Can anyone one explain why a "WITH RECURSIVE" query has the same
results regardless whether UNION or UNION ALL is specified?
broersr=> WITH RECURSIVE t(n) AS (
broersr(> VALUES (1)
broersr(> UNION
broersr(> SELECT n+1 FROM t WHERE n < 100
broersr(> )
broersr-> SELECT sum(n) FROM t;sum
------5050
(1 row)
broersr=> WITH RECURSIVE t(n) AS (
broersr(> VALUES (1)
broersr(> UNION ALL
broersr(> SELECT n+1 FROM t WHERE n < 100
broersr(> )
broersr-> SELECT sum(n) FROM t;sum
------5050
(1 row)
--
Regards,
Richard Broersma Jr.
Visit the Los Angeles PostgreSQL Users Group (LAPUG)
http://pugs.postgresql.org/lapug