I have a problem understanding the part 'ON DUPLICATE KEY UPDATE column_name = VALUES (column_name)
' in my query.
This is my query:
INSERT INTO user_mst(first_name,middle_name,last_name,corp_id,login_name,passwd,emp_num,designation,band_name,corp_mail_id,pers_mail_id,cont_phone,cont_mobile,passport_num,place_of_issue,passport_exp,user_status,user_class,hwc , gender,traveller_email_id,legal_entity)
VALUES(?,?,?,?,?,AES_ENCRYPT(?,?),?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)
ON DUPLICATE KEY UPDATE traveller_email_id = VALUES(traveller_email_id)
I don't understand the part starting from 'On DUPLICATE KEY . . .
".
Please explain.