UPDATE sessions SET
starttime = '9:00',
endtime = '10:30'
WHERE sessionid = 4209;

UPDATE sessions SET
starttime = '11:30',
endtime = '13:00'
WHERE sessionid = 4111;

UPDATE sessions SET
starttime = '14:30',
endtime = '16:00'
WHERE sessionid = 2410;

UPDATE sessions SET
starttime = '16:30',
endtime = '18:00'
WHERE sessionid = 2311;

UPDATE sessions SET
starttime = '14:30',
endtime = '16:00'
WHERE sessionid = 1212;

UPDATE sessions SET
starttime = '11:30',
endtime = '13:00'
WHERE sessionid = 4210;