Magento custom collection filter and sort

We have already know how to filter magento product ,customer,wishlist,order collection fields filters.

But whenever we are working on non-exiting model collection, then we facing problem.Here i have put some tricks how you can filter a custom collection by a field.In post,i have working on a writing how a custom collection is filter by a filed and how the collection will filter.

Suppose a custom collection is

#Mage::getModel('[ModulePrefix/Entities]')->getCollection();
$collection=Mage::getModel('[custommodule/customemodule]')->getCollection();

For add addFieldToSelect('*') at that Collection for retrieves all field value for a module is

Then want to filter that collection by a field name ‘age’ then use

$collection->addFieldToSelect('age');

For add for sort by a specific field then add setOrder('fieldname','SortOrder');
Example want to sort by age descending then try this

$collection->addFieldToSelect('age';'DESC');

for fetch limit number of rows of a collection use setPageSize(number_of_rows)

$collection->setPageSize(10)