I think it would be easier to quote the documentation: 

UNION

Specifies that multiple result sets are to be combined and returned as
+ a single result set.

ALL

Incorporates all rows into the results, including duplicates. If not s
+pecified, duplicate rows are removed.

[download]

/J\

janitored by ybiC: Replace <pre> tags with <code> to avoid lateral scrolling

In reply to Re^3: Perl DBI fetchall_arrayref - puzzling behaviour by gellyfish
in thread Perl DBI fetchall_arrayref - puzzling behaviour by kiat

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