Magento: Filtering a Collection with grouped Clauses

Question

I would like to filter a collection with grouped clauses. In SQL this would look something like:

SELECT * FROM `my_table` WHERE col1=\'x\' AND (col2=\         


        

Answer 1

If your collection is an EAV type then this works well:

$collection = Mage::getResourceModel('yourmodule/model_collection')
    ->addAttributeToFilter('col1', 'x')
    ->addAttributeToFilter(array(
        array('attribute'=>'col2', 'eq'=>'y'),
        array('attribute'=>'col3', 'eq'=>'z'),
    ));

However if you're stuck with a flat table I don't think addFieldToFilter works in quite the same way. One alternative is to use the select object directly.

$collection = Mage::getResourceModel('yourmodule/model_collection')
    ->addFieldToFilter('col1', 'x');
$collection->getSelect()
    ->where('col2 = ?', 'y')
    ->orWhere('col3 = ?', 'z');

But the failing of this is the order of operators. You willl get a query like SELECT * FROM my_table WHERE (col1='x') AND (col2='y') OR (col3='z'). The OR doesn't take precedence here, to get around it means being more specific...

$collection = Mage::getResourceModel('yourmodule/model_collection')
    ->addFieldToFilter('col1', 'x');
$select = $collection->getSelect();
$adapter = $select->getAdapter();
$select->where(sprintf('(col2 = %s) OR (col3 = %s)', $adapter->quote('x'), $adapter->quote('y')));

It is unsafe to pass values unquoted, here the adapter is being used to safely quote them.

Finally, if col2 and col3 are actually the same, if you're OR-ing for values within a single column, then you can use this shorthand:

$collection = Mage::getResourceModel('yourmodule/model_collection')
    ->addFieldToFilter('col1', 'x')
    ->addFieldToFilter('col2', 'in'=>array('y', 'z'));