Stored Procedure 1

if exists teach.num_from_student;create procedure teach.student_a ( in dept_name varchar),  out int ) beginSelectfromwhere stu_dept=dept_name;end;

using (mysqlconnection conn = new Mysqlconnection ("server = localhost; User id=root;password=;d Atabase=teach "))            {                Mysqlcommand cmd = new Mysqlcommand (" Student_a ", conn);                Cmd.commandtype = CommandType.StoredProcedure;                Mysqlparameter year = new Mysqlparameter ("Dept_name", mysqldbtype.varchar,20);                Year. Direction = ParameterDirection.Input;                Year. Value =this.combobox1.text;                Cmd. Parameters.Add (year);                 Mysqlparameter num = new Mysqlparameter ("Count_num", mysqldbtype.int16);                Num. Direction = ParameterDirection.Output;                Cmd. Parameters.Add (num);                Conn. Open ();                Cmd. ExecuteNonQuery ();                This.label1.Text = num. Value.tostring ();                            }

　　

Stored Procedure 1