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NAME

Tangram::Scalar - map scalar fields

SYNOPSIS

        use Tangram;

        # or
        use Tangram::Core;

        $schema = Tangram::Schema->new(
            classes => { NaturalPerson => { fields => {
                        string => [ qw( name firstName gender ) ],
                        int => [ qw( age ) ],
                        real => [ qw( height weight ) ],

        # or

            classes => { NaturalPerson => { fields => {
                        string =>
                        {
                                name    => { sql => 'VARCHAR(100)' },
                                1stname => { col => 'firstName', sql => 'VARCHAR(100) NULL' },
                                gender  => undef()
                        },

                        # etc etc etc

        use Tangram::RawDate;
        use Tangram::RawTime;
        use Tangram::RawDateTime;

        $schema = Tangram::Schema->new(
            classes => { NaturalPerson => { fields => {
                        rawdatetime => [ qw( birth death ) ],
                        rawdate => [ qw( beginVacation endVacation ) ],
                        rawtime => [ qw( breakfast lunch dinner ) ],

DESCRIPTION

Classes Tangram::String, ::Int and ::Real and ::Ref are responsible for mapping the various subtypes of scalars. The first three mappings are documented here since they differ very little. See Tangram::Ref for information on mapping references.

Classes Tangram::RawDate, ::RawTime and ::RawDateTime are responsible for mapping strings to SQL date or time types. These classes are not imported by Tangram.pm, thus they must be explicitly imported via a use directive.

The three predefined typetags string, int and real are for the corresponding Perl scalar subtypes.

The three predefined typetags rawdate, rawtime and rawdatetime are for mapping strings to SQL date/time types. 'Raw' means that Tangram doesn't attempt to interpret the strings, it merely passes them down to DBI.

Each scalar field is stored in a single column of the table associated to the class.

The persistent fields may be specified either as a hash or as an array of field names.

In the hash form, each entry consists in a field name and an associated option hash. The option hash may contain the following fields:

  • col

  • sql

col sets the name of the column used to store the field's value. This field is optional, it defaults to the persistent field name. Override if the field name is not an acceptable SQL column name.

sql sets the SQL type of the column. Used by Schema::deploy() when initializing a database. Defaults to 'VARCHAR(255) NULL' for strings, 'INT NULL' for ints and 'REAL NULL' for reals.

The persistent fields may also be specified as an array of strings, in which case the defaults are used.