Getting started with Query.apex

Conditions

Most of the time, we want to make a query with conditions, typically querying a record with a specific Id or a lookup field, then we can use the 'addConditionEq' method:

Account account =
    (Account)new Query('Account').
    addConditionEq('Id', '0010l00000QJN3MAAX').
    fetch();

This statement is querying an Account record with Id '0010l00000QJN3MAAX', equivalent to this statement:

Account account =
    [ SELECT Id FROM Account WHERE Id = '0010l00000QJN3MAAX' ];

In previous tutorials we saw another statement which has the same functionality, using the 'byId' method:

Account account =
    (Account)new Query('Account').
    byId('0010l00000QJN3MAAX').
    fetch();

Now let's try querying the accounts owned by the current user:

List accounts =
    new Query('Account').
    addConditionEq('OwnerId', UserInfo.getUserId()).
    run();

equivalent to:

List accounts =
    [ SELECT Id FROM Account WHERE OwnerId = :UserInfo.getUserId() ];

'addConditionEq(String field, Object arg)' is limiting the query with a field equals to the variable 'arg', while Query.apex provides other operators for conditions, including 'addConditionNotEq', 'addConditionIn', 'addConditionNotIn', 'addConditionLt', 'addConditionLe', 'addConditionGt', 'addConditionGe' and 'addConditionLike'.

Examples are:

new Query('Account').
    addConditionNotEq('Name', 'N/A').
    run();

new Query('Account').
    addConditionIn('Name', new Set{'ABC'}).
    run();

new Query('Account').
    addConditionNotIn('Name', new Set{'N/A'}).
    run();

new Query('Account').
    addConditionLt('NumberOfEmployees', 15).
    run();

new Query('Account').
    addConditionLe('NumberOfEmployees', 10).
    run();

new Query('Account').
    addConditionGt('NumberOfEmployees', 5).
    run();

new Query('Account').
    addConditionGe('NumberOfEmployees', 10).
    run();

new Query('Account').
    addConditionLike('Name', '%ABC%').
    run();
Done