Re: Importing files with perl::dbi

Looking at the O'Reilly Perl/DBI book(pg 153, 'Inserting and Updating LONG/LOB columns'), I think it's better if you use bind params with a datatype argument. I have not tried the following code, but it should work:

use  DBI qw(:sql_types);
my $dsn = "DBI:Oracle:foobar";
       my $user = "foobar";
       my $pass = "baz";
       my $textfile = "testing.txt";

       open (TEXT, "$textfile") or die "Couldn't open textfile: $!";
       my $longText = join('', <TEXT>);
       close(TEXT);
       $dbh = DBI->connect($dsn, $user, $pass,{ RaiseError => 1})
          or die "Could not connect to database! $DBI::errstr";

$sth = $$dbh->prepare(
    'INSERT INTO table_name (key_name, long_description) VALUES (?, ?)
+';
$sth->bind_param( 1, 42);
$sth->bind_param(2, $longText, SQL_BLOB);
$sth->execute();
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RE: Re: Importing files with perl::dbi by httptech (Chaplain) on Jun 23, 2000 at 15:30 UTC
My solution already uses bind params in the "do" method. I don't think it's necessarily faster to "prepare" and "execute" than to just "do". However, it is faster to undef $/ and then pass <TEXT> as a scalar than to run "join" on every line and pass the intermediate variable.	[reply]
RE: RE: Re: Importing files with perl::dbi by johannz (Hermit) on Jun 23, 2000 at 18:59 UTC
While normally just using a "do" would be correct, in this case since we are talking about a BLOB, using bind with a datatype is safer. By that I mean, when you execute a "do" with bind parameters inline, you are leaving it up the the DBI interface to figure out the datatype. Sometime it will get it right, but there is no guarentee. By using a "bind_param" call with a datatype you are giving the DBI a strong hint as to how to handle the data. To quote again from the Perl DBI book( pg. 154): Passing SQL_BLOB as the optional TYPE parameter to bind_param() gives the driver a strong hint that you're binding to a LONG/LOB type. Some drivers don't need the hint but it's always a good idea to include it. I keep quoting this book since the authors are Alligator Descartes and Tim Bunce, both of whom have been heavily involved in the design of the DBI interface. I tend to believe what they say about how to use the interface. Your second point about undef-ing $/ and passing in <TEXT> I will concede. On examples I tend to be more verbose since it makes debugging easier since you can easily look at the value of a varible. Looking at a filehandle is distinctly harder. :-)	[reply]
RE: RE: RE: Re: Importing files with perl::dbi by httptech (Chaplain) on Jun 23, 2000 at 19:27 UTC
If you really want to give the driver a hint about what datatype you are passing, you can change the 'undef' in my "do" statement to { TYPE => SQL_BLOB } and it will have the same effect. I could have been more verbose on the example, but the original poster did ask for the fastest way. :) Update: Now that I look at it, he just said the best way, not the fastest. Heh. Oh well.	[reply]