Binds a PHP variable to a corresponding named (not supported by mysqli driver, see comment below) or question
mark placeholder in the SQL statement that was use to prepare the statement. Unlike {@see bindValue()},
the variable is bound as a reference and will only be evaluated at the time
that PDOStatement->execute() is called.
As mentioned above, the named parameters are not natively supported by the mysqli driver, use executeQuery(),
fetchAll(), fetchArray(), fetchColumn(), fetchAssoc() methods to have the named parameter emulated by doctrine.
Most parameters are input parameters, that is, parameters that are
used in a read-only fashion to build up the query. Some drivers support the invocation
of stored procedures that return data as output parameters, and some also as input/output
parameters that both send in data and are updated to receive it.