在Perl中使用DBI来更新一行中的多个字段？

Question

I'm mediocre with perl and new to SQL, so excuse any lameness.

I've got a perl script I'm working on that interacts with a database to keep track of users on IRC. From tutorials I've found, I've been able to create the db, create a table within, INSERT a new record, UPDATE a field in that record, and SELECT/find records based on a field.

The problem is, I can only figure out how to UPDATE one field at a time and that seems inefficient.

The code to create the table:

my $sql = <<'END_SQL';
CREATE TABLE seenDB (
id       INTEGER PRIMARY KEY,
date    VARCHAR(10),
time    VARCHAR(8),
nick    VARCHAR(30) UNIQUE NOT NULL,
rawnick VARCHAR(100),
channel VARCHAR(32),
action  VARCHAR(20),    
message VARCHAR(380)
)
END_SQL

$dbh->do($sql);

And to insert a record using values I've determined elsewhere:

$dbh->do('INSERT INTO seenDB (nick, rawnick, channel, action, message, date, time) VALUES (?, ?, ?, ?, ?, ?, ?)', undef, $nickString, $rawnickString, $channelString, $actionString, $messageString, $dateString, $timeString);

So, when the script needs to update, I'd like to update all of these fiends at once, but right now the only thing that works is one at a time, using syntax I got from the tutorial:

$dbh->do('UPDATE seenDB SET time = ? WHERE nick = ?',
 undef,
 $timeString,
 $nickString);

I've tried the following syntaxes for multiple fields, but they fail:

$dbh->do('UPDATE seenDB (rawnick, channel, action, message, date, time) VALUES (?, ?, ?, ?, ?, ?)', undef, $rawnickString, $channelString, $actionString, $messageString, $dateString, $timeString);

and

$dbh->do('UPDATE seenDB SET rawnick=$rawnickString  channel=$channelString   action=$actionString   message=$messageString   date=$dateString  time=$timeString WHERE nick=$nickString');

Is there a better way to do this?

Answer 1

You can update several fields at once in pretty much the same way as you update a single field, just list them comma separated in the update, something like;

$dbh->do('UPDATE seenDB SET rawnick=?, channel=?, action=?, message=?, date=?, time=? WHERE nick=?',
    undef,
    $rawnickString,
    $channelString,
    $actionString, 
    $messageString,
    $dateString,
    $timeString,
    $nickString
);