hi ,I started to implement a attendance system. I need to render a view as matrix such that colums specify dates and rows specify student names. Their intersection represents existence of the student at that date in lecture.
i have tables:
CREATE TABLE AttendanceList (
alid int(11) NOT NULL AUTO_INCREMENT,
attendancedate date DEFAULT NULL,
duration int(11) DEFAULT NULL,
courseid int(11) DEFAULT NULL,
PRIMARY KEY (alid),
KEY courseid (courseid)
)
and
CREATE TABLE AttendanceInfo (
aid int(11) NOT NULL AUTO_INCREMENT,
studentid int(11) DEFAULT NULL,
studentname char(40) DEFAULT NULL,
attendancelistid int(11) DEFAULT NULL,
PRIMARY KEY (aid),
KEY attendancelistid (attendancelistid)
)
i am using to get data from these tables
SELECT studentname, attendancedate
FROM AttendanceInfo i
JOIN (
SELECT *
FROM AttendanceList
WHERE courseid =498
)l ON i.attendancelistid = l.alid
thanks in advance.