Query Generator is a class that will easily generate complex SQL queries for us. It will permit us to define some high-level fields and conditions and return all the necessary joins and conditions to get the information we need.

Besides giving us all the joins we need to get the information we are looking for it will also optimize the query to be as low cost as possible.

The best place to start is in the unit tests. The Query Generator unit tests show a full set of the different ways this powerful class can be used.

The filter syntax is a rather complex structure that was created before we had Query Generator so it is used throughout the application. When QG was created it was given a set of methods to directly convert the filter syntax into the QG syntax. Two of those functions are useful as a “different” way to load conditions into a Query Generator object.

constructAdvancedSearchConditions will return the coreBOS List Filter syntax from an array of fields and conditions. The structure returned from this method can be directly fed into the method addUserSearchConditions to set the query conditions.

Here are two examples and you can see a few more in the unit tests.

$queryGenerator = new QueryGenerator('Accounts', $current_user);
$conds = array(
	array(
		array(
			'field' => 'accountname',
			'op' => 'c',
			'value' => 'al',
			'glue' => '',
		),
	),
);
$filter = $queryGenerator->constructAdvancedSearchConditions('Accounts', $conds);
$queryGenerator->addUserSearchConditions($filter);
// user querygenerator normally, the conditions are set
// where accountname like '%al%'

$queryGenerator = new QueryGenerator('Accounts', $current_user);
$conds = array(
	array(
		array(
			'field' => 'accountname',
			'op' => 'c',
			'value' => 'al',
			'glue' => 'and',
		),
		array(
			'field' => 'employees',
			'op' => 'g',
			'value' => '15',
			'glue' => '',
		),
	),
);
$filter = $queryGenerator->constructAdvancedSearchConditions('Accounts', $conds);
$queryGenerator->addUserSearchConditions($filter);
// user querygenerator normally, the conditions are set
// where accountname like '%al%' and employees > 15