CREATE TABLE Students (student_id INT, date_of_registration DATETIME, date_of_latest_logon DATETIME, login_name VARCHAR, password VARCHAR, personal_name VARCHAR, middle_name VARCHAR, family_name VARCHAR)
CREATE TABLE Courses (course_id INT, author_id INT, subject_id INT, course_name VARCHAR, course_description VARCHAR)
CREATE TABLE Subjects (subject_id INT, subject_name VARCHAR)
CREATE TABLE Course_Authors_and_Tutors (author_id INT, author_tutor_ATB VARCHAR, login_name VARCHAR, password VARCHAR, personal_name VARCHAR, middle_name VARCHAR, family_name VARCHAR, gender_mf VARCHAR, address_line_1 VARCHAR)
CREATE TABLE Student_Tests_Taken (registration_id INT, date_test_taken DATETIME, test_result VARCHAR)
CREATE TABLE Student_Course_Enrolment (registration_id INT, student_id INT, course_id INT, date_of_enrolment DATETIME, date_of_completion DATETIME)

A bar chart for what are the number of the dates of the latest logon of the students with family name 'Jaskolski' or 'Langosh'?, and order total number in asc order.
SELECT date_of_latest_logon, COUNT(date_of_latest_logon) FROM Students WHERE family_name = "Jaskolski" OR family_name = "Langosh" ORDER BY COUNT(date_of_latest_logon)
SELECT "date_of_latest_logon", COUNT("date_of_latest_logon") FROM "Students" WHERE "Jaskolski" = "family_name" OR "Langosh" = "family_name" ORDER BY COUNT("date_of_latest_logon") NULLS FIRST