NAME

Norma::ORM::Collection - Queries and results with metadata from Norma::ORM::Mappable classes

SYNOPSIS

  my $uk_customers = Norma::ORM::Collection->new(
	class => 'MyApp::Customer',
	where => { country => 'UK' },
  );

  for my $customer ($uk_customers->items) {
  	...
  }

METHODS

new(where => {...} order => $column_name, ...)

Queries the database and returns a collection which contains an array of instantiated objects, along with other metadata. We'll take the following parameters:

parameters

join

Specify join clauses as hashrefs, table names (or derived tables / sub queries if you like) pointing to column associations.

  join => [ 
  	customer_notes 
		=> 'customer_notes.customer_id = customers.id',

	'(select customer_id, min(order_date) first_order_date from orders group by customer_id) first_order_dates' 
		=> 'first_order_dates.customer_id = customers.id'
  ]

where

Criteria for the "where" clause may be specified in a number of ways. For simple lookups, key / value pairs will suffice. To find customers in London, you might try:

where => { 
	city => 'London', 
	country => 'UK',
}

For comparisons other than equality, sepcify the sql comparison in the key itself. To find customers in Eastern Central London by postcode, you might try:

where => { 
	'postal_code like' => 'EC%', 
	country => 'UK' 
}

If you need more flexibility, you can pass in your own where clauses along-with:

  where => [
	q{ postal_code between 'EC2' and 'EC4' },
	{ country => 'UK' },
  ]

Outside of custom where clauses, values will be quoted by DBI::quote.

order => $order_clause

Order the query according to this clause, if specified

limit_count

Return this many items

limit_offset

Return items starting at this offset

METHODS

items

Array of objects where each one is an instance of the given $class

total_count

The number of rows that matched this query

query

The actual SQL query that was run

class

The name of the class of the objects returned via items