Error code handling in perl

Hi all,

I am populating a table in postgres, writing the script in perl (using DBI),
and I am trying to do some error handling. For example - this should return
an error due to unique violation:
>$sth=$conn->prepare("INSERT INTO tablename (names) values ($name)") or die
"error1 is: ".$sth->err;

>$sth->execute() or do{
> print "state is: ".$sth->state."\n";
> print "err is: ".$sth->err."\n";
>};

I always get the same SQLSTATE and ERROR, no matter what the error is:

>state is: S1000
>err is: 7

although in the documentation it says that the error code is "23505" (unique
violation).
Is there no way to identify the error by code from postgres via perl?

Thanks,
Elinor

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