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From Richard Broersma
Subject Learning about WITH RECURSIVE
Date
Msg-id 396486430911041403u639c750bn488ada60822448c0@mail.gmail.com
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Responses Re: Learning about WITH RECURSIVE  (Tom Lane <tgl@sss.pgh.pa.us>)
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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.

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