in reply to converting from some database format do Berkeley DB.

The module DBD::DBM supports BerkeleyDB. That means that you can use DBI to select from any database source (including CSV and MySQL) and insert into a BerkeleyDB database. You could also just use DBI's selectall_hashref() to load the data source into a hash and then tie that to your BerkeleyDB.
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Re^2: converting from some database format do Berkeley DB.
by pc2 (Beadle) on Jul 19, 2007 at 12:05 UTC
    salutations, thank you for the response, jZed. we installed the DBD:CSV module via ActivePerl's package manager, then we wrote the following DBI:CSV code, which uses ";" as a text delimiter: 
        use DBI;
    $dbh = DBI->connect(qq{DBI:CSV:csv_sep_char=\\;});
    $dbh->{'csv_tables'}->{'dict'} = { 'file' => 'dict.txt'};
    $sth = $dbh->prepare("SELECT * FROM dict");
    $sth->execute() or die "Cannot execute: " . $sth->errstr();

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    how can we proceed to transform the table "dict" (which is the "dict.txt" file) into a BerkeleyDB file? is some other module necessary? note: the $dbh->prepare() and $sth->execute() lines in this code seem to be too slow; may that be because the dict file is too big (385090 lines)? thank you in advance.
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      Hi. A little detective work lead me to your previous posting which supplies some context for your question here. Yes, DBD::CSV will be slow with a file as large as the one you are dealing with. The fastest way to get your data from a CSV file into a quickly-searchable form is to use the loading mechanism of a database (for example LOAD INFILE with MySQL). Using a database would also simplify and speed up future updates and searches. If you absolutely must use BerekeleyDB instead of a database, then you can convert from CSV to BerekeleyDB with something like this: 
      #!/usr/bin/perl
use warnings;
use strict;
use BerkeleyDB;

my( $csv_file, $berk_file) = qw( dict.txt dict );
my $db = BerkeleyDB::Hash->new(
    -Filename => $berk_file,
    -Flags    => DB_CREATE
) or die "Cannot open file '$berk_file': $! $BerkeleyDB::Error\n";
open( DICTE, $csv_file )
  or die "Cannot open file '$csv_file': $!\n";

for (<DICTE>) {
    chomp;
    my($key, $value) = split(/;/,$_,2);
    $db->db_put($key,$value);
}

# the file "dict" is now a BerkeleyDB file with entire
# contents of the CSV file "dict.txt"

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