It seems that you are inserting data directly into the data list in jsp. Insertion failed for many reasons, and you didn't send an error message to the console. First, you should check whether your sql statement format is correct, and then feel STMT. Execute Update (SQL); If there is a problem, what is the significance of the res returned? Generally use stmt.execute (SQL); The return value is Boolean, and if it is true, the data insertion is successful; Also, take a look at the database-driven import, and it is best to give the error message of the console.

//There is something wrong with //sql splicing//,and it should be changed to (missing'):

String SQL = "insert into EMP (us name, salary, email, EmployedDates, department met) values ("+usn+ ","+sal+ ","+email+ ","+date+ ",+department met+") ";