Greetings all,
This is a smallish issue and not a mission critical one (at least not for me), but I was wondering about the difference in behavior for UPDATE|DELETE|INSERT queries in DBI. Here is the issue. I am running MySQL 4.0 and have noticed over the past few months that return values from DBI calls differ depending on how the query is executed. example: 
###idiosyncratic paranoid method wherein I prepare everything.
my $sth = $dbh->prepare("UPDATE mytable SET value1=?, value2=? WHERE i
+d=?") || die $dbh->errstr;
my $update_success = $sth->execute($val1,$val2,$id) || die $sth->errst
+r;

###non paranoid method cleaner as well.
my $update_success = $dbh->do("UPDATE mytable SET value1='$val1', valu
+e2='$val2' WHERE id=$id") || die $dbh->errstr;

[download]
The issue arises when checking the value of $update_success. The first method does not return a value consistently (at least not consistently enough for me to code with). Where as the latter method returns a value but does not allow for the flexibility of the first method, and the query must be recreated with each successive call.
So, Is there something I am missing or shouldn't both methods return a value? I have already realized that the update failure returns "0E0" and not just "0" as I had originally thought, but aside from this why does preparing any type of query other than a "SELECT" not return values? Should I be checking some property of the statement handle? the database handle? or am I stuck not preparing non-select queries? Has anyone else come across this behavior as well?
Thank you all in advance.
-injunjoel

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

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