INSERT INTO TABLE2 (COLUMN1, COLUMN2, COLUMN3)
SELECT COLUMN1, COLUMN2, COLUMN3
FROM TABLE1 WHERE COLUMN4='FOOBAR'

##</code><code>##

...
my $statement = 
     "INSERT INTO TABLE2 (COLUMN1, COLUMN2, COLUMN3) \n".
     "SELECT COLUMN1, COLUMN2, COLUMN3 \n".
     "FROM TABLE1 WHERE COLUMN4=?";
my $rv  = $dbh->do($statement, {}, 'foo');

##</code><code>##

...
my $statement = 
     "INSERT INTO TABLE2 (COLUMN1, COLUMN2, ".
     my_subrt(COLUMN3) .") \n".
     "SELECT COLUMN1, COLUMN2, COLUMN3 \n".
     "FROM TABLE1 WHERE COLUMN4=?";
my $rv  = $dbh->do($statement, {}, 'foo');