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CREATE TABLE mytable
(`staff_id` int, `Name` varchar(5), `Monday` varchar(13), `Tuesday` varchar(13))
;
INSERT INTO mytable
(`staff_id`, `Name`, `Monday`, `Tuesday`)
VALUES
(1, 'Mark', '8:00am-5:00pm', '9:00am-6:00pm'),
(2, 'Steve', '9:00am-6:00pm', '7:00am-4:00pm')
;
UPDATe mytable SET Monday = "8:00am-1:00pm"
WHERE Monday= "8:00am-5:00pm";
UPDATe mytable SET Monday = "8:00am-1:00pm"
WHERE Monday= "9:00am-6:00pm";
SELECT * FROM mytable
| staff_id | Name | Monday | Tuesday |
|---|---|---|---|
| 1 | Mark | 8:00am-1:00pm | 9:00am-6:00pm |
| 2 | Steve | 8:00am-1:00pm | 7:00am-4:00pm |