UPDATE categories

SET display_order = CASE id

WHEN 1 THEN 3

WHEN 2 THEN 4

WHEN 3 THEN 5

ELSE display_order

END,

title = CASE id

WHEN 1 THEN 'New Title 1'

WHEN 2 THEN 'New Title 2'

WHEN 3 THEN 'New Title 3'

ELSE title

END

WHERE id IN (1,2,3)

INSERT INTO test_tbl (id,dr) VALUES (1,'2'),(2,'3'),...(x,'y') ON DUPLICATE KEY UPDATE dr=VALUES(dr);

INSERT INTO test_tbl

(`license_id`, `serial`, `username`, `time`)

VALUES

('SDOHFOEI305', 'No.16NOVBJ005', 'A', 'November 19, 2016'),

('SDOHFOEI308', 'No.16NOVBJ008', 'B', 'November 19, 2016'),

('SDOHFOEI318', 'No.16NOVBJ018', 'C', 'November 19, 2016')

ON DUPLICATE KEY UPDATE

serial=VALUES(serial),

username=VALUES(username),

time=VALUES(time)

UPDATE `tablename` SET `field` = `field` + FLOOR(10 + RAND() * (100 - 10 + 1)) WHERE `id` IN (1, 2, 3);

SELECT CONCAT(ROUND(SUM(`data_length` / 1024 / 1024), 2), 'MB') AS data_length_MB,

CONCAT(ROUND(SUM(`index_length` / 1024 / 1024), 2), 'MB') AS index_length_MB

FROM `information_schema`.`tables`

WHERE `TABLE_SCHEMA` = 'dbname' AND `TABLE_NAME` = 'tablename';

SELECT A.ID FROM A LEFT JOIN B ON A.ID=B.ID WHERE B.ID IS NULL;

SELECT * FROM B WHERE (SELECT COUNT(1) AS NUM FROM A WHERE A.ID = B.ID) = 0;