SQL::Entity::Column - Entity column abstraction.

SQL-Entity documentation Contained in the SQL-Entity distribution.

Index

Code Index:

NAME

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SQL::Entity::Column - Entity column abstraction.

SYNOPSIS

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    use SQL::Entity::Column ':all';

    my $column = SQL::Entity::Column->new(name  => 'name');
    or 
    my $column = sql_column(name  => 'name');

DESCRIPTION

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Represents entities column, that maps to the table column, or sql expression.

EXPORT

None by default.

sql_column by tag 'all'

ATTRIBUTES

id

Column alias

name
table

Table association

entity

Entity association

expression

Column expression: f.e. col1 || col2

case_sensitive
queryable

Flag is column can be use in where caluse

insertable
update_allowed
unique

METHODS

initialise
as_string
subquery_to_string
as_operand

Returns column as condition operand.

sql_column

COPYRIGHT

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The SQL::Entity::Column module is free software. You may distribute under the terms of either the GNU General Public License or the Artistic License, as specified in the Perl README file.

SEE ALSO

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SQL::Entity SQL::Entity::Table SQL::Entity::Condition

AUTHOR

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Adrian Witas, adrian@webapp.strefa.pl

SQL-Entity documentation Contained in the SQL-Entity distribution. 
package SQL::Entity::Column;

use strict;
use warnings;
use vars qw(@EXPORT_OK %EXPORT_TAGS $VERSION);

$VERSION = '0.02';

use Abstract::Meta::Class ':all';
use base 'Exporter';

@EXPORT_OK = qw(sql_column);
%EXPORT_TAGS = (all => \@EXPORT_OK);


has '$.id';



has '$.name';



has '$.table' => (associated_class => 'SQL::Entity::Table');


has '$.entity' => (associated_class => 'SQL::Entity');



has '$.expression';



has '$.case_sensitive' => (default => 1);



has '$.queryable' => (default => 1);



has '$.insertable' => (default => 1);



has '$.updatable' => (default => 1);



has '$.unique';



sub initialise {
    my ($self) = @_;
    $self->set_id($self->name) unless $self->id;
    if ($self->expression) {
        $self->insertable(0);
        $self->updatable(0);
    }
}



sub as_string {
    my ($self, $source, $join_methods) = @_;
    my $table = $self->table;
    return $self->subquery_to_string($source, $join_methods)
      if ($table && $source && $table ne $source);
    my $table_alias = $table ?  $table->alias . "." : '';
    my $id = $self->id;
    my $expression = $self->expression;
    my $name = $self->name;
    my $result = ($expression ? "($expression)" : $table_alias . $name);
    $result . ($id && $id ne ($name || '') ? " AS $id": '');
}



sub subquery_to_string {
    my ($self, $source, $join_methods) = @_;
    return () unless $self->entity;
    my $table = $self->table;
    my $id = $self->id;
    my $table_alias = $table ?  $table->alias . "." : '';
    my $table_id = $table->id;
    my $relationship = $self->entity->to_one_relationship($table_id);
    my $join_method = $join_methods->{$table_id};
    unless ($join_method) {
        #enforce subquery
        my ($sql, $bind_variable) = $table->query([$id], $relationship->join_condition($self->entity), undef, {$source->id => 'SUBQUERY'});
        
        return "($sql) AS $id";
    } else {
        $self->as_string;
    }
}



sub as_operand {
    my $self = shift;
    my $table = $self->table;
    my $table_alias = $table ?  $table->alias . "." : '';
    my $case_sensitive = $self->case_sensitive;
    (! $case_sensitive ? 'UPPER(' : '')
      . $table_alias . ($self->name || $self->expression)
      . (! $case_sensitive ? ')' : '');
}


sub sql_column {
    __PACKAGE__->new(@_);
}


1;

__END__