Henrik Nilsson wrote:
>> What Perl binary hash file? I was referring to the contents of the
>> database (tables, procedures, constraints, etc). If you have a binary
>> object stored in the dB, export/import won't make it portable.
>
> No, this was no Oracle database matter but a Perl hash file (which I
> think is in binary format) matter. Sorry, perhaps I didn't make this
> clear. So the problem is really, how to make such a file work on
> another os...?
1) If you can get the data you need out of Oracle, use its
exp/imp programs, otherwise:
2) If you're trying to move a small DBM file (one of the AnyDBM_File
derivatives) from one platform to another, follow these steps. By
"small", I mean that it will fit in your system's virtual memory.
A) Open the database with tie() like usual.
# replace "SOME_File" with the right module name.
tie my %database, 'SOME_File', 'filename', ...
B) use Storable's nstore to store a portable binary representation:
# note, you cannot store by reference, you must make a copy.
use Storable qw(nstore);
nstore({%database}, 'filename.bin') || die $!;
C) On the destination system, use Storable's retrieve to load the
data, and put it back into the database.
use Storable qw(retrieve);
$db_data = retrieve('filename.bin') || die $!;
%database = %$db_data;
3) If you're trying to move a *large* DBM file (larger than will fit in
virtual memory), you'll need to dump it a little at a time. Using a
CSV file is an option:
A) Open the database with tie() like usual.
# replace "SOME_File" with the right module name
tie my %database, 'SOME_File', 'filename', ...
B) Iterate over the name/value pairs (using "each" -- not "keys"), and
store each one in the CSV file.
use Text::CSV_XS;
my $csv = Text::CSV_XS->new(); # be sure to read perldoc
while (my ($k,$v) = each %database) {
$csv->combine($k,$v)
|| die "can't combine row for key '$k'";
print OUTFILE $csv->string(), "\n";
}
C) On the destination system, read the CSV file and populate the
database file with its contents.
use Text::CSV_XS;
my $csv = Text::CSV_XS->new();
while (<>) {
$csv->parse($_) || die "can't parse line $.";
my ($k,$v) = $csv->fields;
$database{$k} = $v;
}
Regards,
Philip
