NAME

Tangram::PerlDump - map any Perl object as scalar dump

SYNOPSIS

use Tangram::Core;
use Tangram::PerlDump; # always

$schema = Tangram::Schema->new(
   classes => { NaturalPerson => { fields => {

   perl_dump =>
   {
      diary => # diary is a perl hash 
      {
         col => 'diarydata',
         sql => 'TEXT',
         indent => 0,
         terse => 1,
         purity => 0
      },

      lucky_numbers => 'int', # use defaults
   }

DESCRIPTION

Maps arbitrary Perl data structures by serializing to a string representation. The persistent fields are grouped in a hash under the perl_dump key in the field hash.

Serialization is done by Data::Dumper, which traverses the Perl data structure and creates a string representation of it. The resulting string will be mapped to the DBMS as a scalar value. During restore, the scalar value will be eval'd to reconstruct the original data structure.

As Data::Dumper might not handle persistent references correctly, the data structure may only contain "normal" Perl references.

The field names are passed in a hash that associates a field name with a field descriptor. The field descriptor may be either a hash or a string. The hash uses the following fields:

• col

• sql

• indent

• terse

• purity

The optional fields col and sql specify the column name and the column type for the scalar value in the database. If not present, col defaults to the field name and sql defaults to VARCHAR(255). Values will be always quoted as they are passed to the database.

The remaining optional fields control the serialization process. They will be passed down to Data::Dumper as values to the corresponding Data::Dumper options. The default settings are: no indentation (indent=0), compact format (terse=1), and quick dump (purity=0).

AUTHOR

This mapping was contributed by Gabor Herr <herr@iti.informatik.tu-darmstadt.de>