The difference is the type of queries, not how you call them. Update, delete, etc queries will all return a fixed number of rows they affected. Select queries will not as the database has no idea how many rows it affects until it has finished the statement. This is a basic database design issue, probably for optimization purposes. It's in the dbi docs last I checked.

In reply to Re: Return values from $dbh->do vs. $sth->execute(); by BUU
in thread Return values from $dbh->do vs. $sth->execute(); by injunjoel

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