Only the second way will work. The first is for finding how many rows were affected by an UPDATE/DELETE operation.

Since DBD::Oracle uses the same libraries as SQL*Plus, that strongly leads me to look at some difference between the Perl invocation and the SQL*Plus invocation: how the queries are constructed, who is creating the query, how are the results fetched.

Also, what happens when you issue a SELECT COUNT(*) FROM foo WHERE ... in each of the environments?

Chris
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