added Üz 12

Uebungszettel_12.sql

@@ -0,0 +1,204 @@
+--Aufgabe 12.1
+CREATE OR REPLACE PACKAGE manage_students
+AS
+  v_current_date DATE;
+
+  PROCEDURE find_sname
+  (i_student_id IN student.student_id%TYPE,
+  o_first_name OUT student.first_name%TYPE,
+  o_last_name OUT student.last_name%TYPE
+  );
+
+  PROCEDURE display_student_count;
+  
+  FUNCTION id_is_good
+  (i_student_id IN student.student_id%TYPE)
+  RETURN BOOLEAN;
+END manage_students;
+/
+-- a) Es wird eine Package SPECIFICATION gemacht.
+
+DECLARE
+  v_first_name student.first_name%TYPE;
+  v_last_name student.last_name%TYPE;
+BEGIN
+  manage_students.find_sname(125, v_first_name, v_last_name);
+  DBMS_OUTPUT.PUT_LINE(v_first_name||' '||v_last_name);
+END;
+/
+-- b) Es kommt ein Error da noch kein Body für manage_students gemacht wurde. 
+
+
+--Aufgabe 12.2
+CREATE OR REPLACE PACKAGE BODY manage_students
+AS
+  PROCEDURE find_sname
+  (i_student_id IN student.student_id%TYPE,
+  o_first_name OUT student.first_name%TYPE,
+  o_last_name OUT student.last_name%TYPE)
+  IS
+    v_student_id student.student_id%TYPE;
+  BEGIN
+    SELECT first_name, last_name
+    INTO o_first_name, o_last_name
+    FROM student
+    WHERE student_id = i_student_id;
+  EXCEPTION
+    WHEN OTHERS THEN
+      DBMS_OUTPUT.PUT_LINE('Error in finding student_id: '||v_student_id);
+  END find_sname;
+
+  FUNCTION id_is_good
+  (i_student_id IN student.student_id%TYPE)
+  RETURN BOOLEAN
+  IS
+    v_id_cnt number;
+  BEGIN
+    SELECT COUNT(*)
+    INTO v_id_cnt
+    FROM student
+    WHERE student_id = i_student_id;
+    
+	RETURN 1 = v_id_cnt;
+  EXCEPTION
+    WHEN OTHERS THEN
+      RETURN FALSE;
+  END id_is_good;
+END manage_students;
+/
+
+-- a) der Body für die vorherige SPECIFICATION manage_students wird erstellt.
+
+--b)
+DECLARE
+    o_first_name student.first_name%TYPE;
+    o_last_name student.last_name%TYPE;
+    v_return_value BOOLEAN;
+BEGIN
+    manage_students.find_sname(5, o_first_name, o_last_name);
+    v_return_value := manage_students.id_is_good(101);
+END;
+/
+
+
+--Aufgabe 12.3
+CREATE OR REPLACE PACKAGE BODY manage_students
+AS
+  PROCEDURE find_sname
+  (i_student_id IN student.student_id%TYPE,
+  o_first_name OUT student.first_name%TYPE,
+  o_last_name OUT student.last_name%TYPE)
+  IS
+    v_student_id student.student_id%TYPE;
+  BEGIN
+    SELECT first_name, last_name
+    INTO o_first_name, o_last_name
+    FROM student
+    WHERE student_id = i_student_id;
+  EXCEPTION
+    WHEN OTHERS THEN
+      DBMS_OUTPUT.PUT_LINE('Error in finding student_id: '||v_student_id);
+  END find_sname;
+
+  FUNCTION id_is_good
+  (i_student_id IN student.student_id%TYPE)
+  RETURN BOOLEAN
+  IS
+    v_id_cnt number;
+  BEGIN
+    SELECT COUNT(*)
+    INTO v_id_cnt
+    FROM student
+    WHERE student_id = i_student_id;
+    
+	RETURN 1 = v_id_cnt;
+  EXCEPTION
+    WHEN OTHERS THEN
+      RETURN FALSE;
+  END id_is_good;
+
+  FUNCTION get_num_students
+  RETURN NUMBER
+  IS
+    v_id_cnt number;
+  BEGIN
+    SELECT COUNT(*)
+    INTO v_id_cnt
+    FROM student;
+    
+	RETURN v_id_cnt;
+  END get_num_students;
+
+  PROCEDURE display_student_count
+  IS
+  BEGIN
+    DBMS_OUTPUT.PUT_LINE(get_num_students);
+  END display_student_count;
+
+END manage_students;
+/
+
+BEGIN
+    manage_students.display_student_count;
+END;
+/
+
+--Aufgabe 12.4
+CREATE OR REPLACE PACKAGE BODY manage_students
+AS
+  PROCEDURE find_sname
+  (i_student_id IN student.student_id%TYPE,
+  o_first_name OUT student.first_name%TYPE,
+  o_last_name OUT student.last_name%TYPE)
+  IS
+    v_student_id student.student_id%TYPE;
+  BEGIN
+    SELECT first_name, last_name
+    INTO o_first_name, o_last_name
+    FROM student
+    WHERE student_id = i_student_id;
+  EXCEPTION
+    WHEN OTHERS THEN
+      DBMS_OUTPUT.PUT_LINE('Error in finding student_id: '||v_student_id);
+  END find_sname;
+
+  FUNCTION id_is_good
+  (i_student_id IN student.student_id%TYPE)
+  RETURN BOOLEAN
+  IS
+    v_id_cnt number;
+  BEGIN
+    SELECT COUNT(*)
+    INTO v_id_cnt
+    FROM student
+    WHERE student_id = i_student_id;
+    
+	RETURN 1 = v_id_cnt;
+  EXCEPTION
+    WHEN OTHERS THEN
+      RETURN FALSE;
+  END id_is_good;
+
+  FUNCTION get_num_students
+  RETURN NUMBER
+  IS
+    v_id_cnt number;
+  BEGIN
+    SELECT COUNT(*)
+    INTO v_id_cnt
+    FROM student;
+    
+	RETURN v_id_cnt;
+  END get_num_students;
+
+  PROCEDURE display_student_count
+  IS
+  BEGIN
+    DBMS_OUTPUT.PUT_LINE(get_num_students);
+  END display_student_count;
+  
+BEGIN
+    v_current_date := trunc(sysdate, 'DD');
+
+END manage_students;
+/