PL/SQL复习

 DESC STUDENTTABLE
SET SERVEROUTPUT ON;
declare 
v_str1 VARCHAR2(10);
v_str2 VARCHAR2(50);
begin
  v_str1:='hello';
  select STUDENT_NAME into v_str2 from STUDENTTABLE where STUDENT_NO=1;
  dbms_output.put_line(v_str1 ||', '|| v_str2);
  
  EXCEPTION
    WHEN NO_DATA_FOUND THEN
      dbms_output.put_line('NO DATA FOUND');
end;
-------------------

--------------------------------------------------------VIEW-----------------------------------------------
--------------------------------------------------------VIEW-----------------------------------------------
--------------------------------------------------------VIEW-----------------------------------------------
--------------------------------------------------------VIEW-----------------------------------------------
---------CREATE A VIEW
CREATE OR REPLACE VIEW TEST_VIEW
AS
SELECT * FROM STUDENTTABLE WHERE ROWNUM<10;
--QUERY DATA FROM TEST_VIEW
SELECT * FROM TEST_VIEW;
-----DROP VIEW
DROP VIEW TEST_VIEW;

--------------------------------------------------------SYNONYM-----------------------------------------------
--------------------------------------------------------SYNONYM-----------------------------------------------
--------------------------------------------------------SYNONYM-----------------------------------------------
--------------------------------------------------------SYNONYM-----------------------------------------------
CREATE SYNONYM SYN_PHRASES FOR CITIAP_USER; --HERE I LOGIN AS JFPAP USER TO CREATE A SYNONYM FOR CITIAP USER, TABLE WAS CREATED BY CITIAP USER.
GRANT ALL ON CITIAP.PHRASES TO JFPAPUSER;-- HERE I LOGIN AS CITIAP USER TO GRANT TABLE PHRASES TO JFPAP USER

--------------------------------------------------------SEQUENCE-----------------------------------------------
--------------------------------------------------------SEQUENCE-----------------------------------------------
--------------------------------------------------------SEQUENCE-----------------------------------------------
--------------------------------------------------------SEQUENCE-----------------------------------------------
--CREATE A SEQUENCE
CREATE SEQUENCE MY_SEQ INCREMENT BY 1 START WITH 1 MAXVALUE 10;
CREATE SEQUENCE MY_SEQ;
--DROP SEQUENCE
DROP SEQUENCE MY_SEQ;
--QUERY SEQUECE VALUE
SELECT MY_SEQ.CURRVAL FROM DUAL;--CURRENT VALUE
SELECT MY_SEQ.NEXTVAL FROM DUAL;--NEXT VALUE

--------------------------------------------------------PL/SQL BLOCK-----------------------------------------------
--------------------------------------------------------PL/SQL BLOCK-----------------------------------------------
--------------------------------------------------------PL/SQL BLOCK-----------------------------------------------
--------------------------------------------------------PL/SQL BLOCK-----------------------------------------------
DECLARE 
  V_STUDENT_NAME VARCHAR2(50);
BEGIN
  select STUDENT_NAME into V_STUDENT_NAME from STUDENTTABLE where STUDENT_NO=&NO;
  dbms_output.put_line(V_STUDENT_NAME);
END;


--------------------------------------------------------PROCEDURE-----------------------------------------------
--------------------------------------------------------PROCEDURE-----------------------------------------------
--------------------------------------------------------PROCEDURE-----------------------------------------------
--------------------------------------------------------PROCEDURE-----------------------------------------------
CREATE OR REPLACE PROCEDURE UPDATE_NAME(NEWSTUNAME VARCHAR2,STUNO VARCHAR2) IS
V_NAME VARCHAR2(10);
BEGIN
  UPDATE STUDENTTABLE SET STUDENT_NAME=NEWSTUNAME WHERE student_no=STUNO;
  COMMIT;
  SELECT STUDENT_NAME INTO V_NAME FROM studenttable WHERE student_no=STUNO;
  dbms_output.put_line('NAME WAS UPDATED, NEW NAME IS '|| V_NAME);
END;
CALL UPDATE_NAME('??','1');

--------------------------------------------------------FUNCTION-----------------------------------------------
--------------------------------------------------------FUNCTION-----------------------------------------------
--------------------------------------------------------FUNCTION-----------------------------------------------
--------------------------------------------------------FUNCTION-----------------------------------------------
CREATE OR REPLACE FUNCTION FINDSTUNAME(STU_NO   VARCHAR2)RETURN VARCHAR2 is 
  STU_NAME STUDENTTABLE.STUDENT_NAME%TYPE;
BEGIN
  SELECT STUDENT_NAME INTO STU_NAME FROM STUDENTTABLE WHERE student_no=STU_NO;
  RETURN STU_NAME;
END;

 

--------------------------------------------------------PACKAGE-----------------------------------------------
--------------------------------------------------------PACKAGE-----------------------------------------------
--------------------------------------------------------PACKAGE-----------------------------------------------
--------------------------------------------------------PACKAGE-----------------------------------------------
CREATE OR REPLACE PACKAGE STU_PKG AS
  PROCEDURE PROCEDURE UPDATE_NAME (NEWSTUNAME VARCHAR2 , STUNO VARCHAR2) ;
  FUNCTION FINDSTUNAME ( STU_NO   VARCHAR2 ) RETURN VARCHAR2 ;
 END ;
 
 --PACKAG BODY
CREATE PACKAGE BODY STU_PKG_BODY IS
  PROCEDURE UPDATE_NAME(NEWSTUNAME VARCHAR2,STUNO VARCHAR2) IS
V_NAME VARCHAR2(10);
BEGIN
  UPDATE STUDENTTABLE SET STUDENT_NAME=NEWSTUNAME WHERE student_no=STUNO;
  COMMIT;
  SELECT STUDENT_NAME INTO V_NAME FROM studenttable WHERE student_no=STUNO;
  dbms_output.put_line('NAME WAS UPDATED, NEW NAME IS '|| V_NAME);
END;
FUNCTION FINDSTUNAME(STU_NO   VARCHAR2)RETURN VARCHAR2 is 
  STU_NAME VARCHAR2(10) ;
BEGIN
  SELECT STUDENT_NAME INTO STU_NAME FROM STUDENTTABLE WHERE student_no=STU_NO;
  RETURN STU_NAME;
END;
END;

--------------------------------------------------------TRIGGER-----------------------------------------------
--------------------------------------------------------TRIGGER-----------------------------------------------
--------------------------------------------------------TRIGGER-----------------------------------------------
--------------------------------------------------------TRIGGER-----------------------------------------------
CREATE OR REPLACE TRIGGER UPDATE_STU_TRIGGER
BEFORE INSERT  
ON STUDENTTABLE
FOR EACH ROW
BEGIN
 
    SELECT MY_SEQ.NEXTVAL  INTO :NEW.STUDENT_NO FROM DUAL;
  
END;
 insert into STUDENTTABLE(student_name) values('hello');
 commit;
 select * from STUDENTTABLE;
--------------------------------------------------------IF-----------------------------------------------
--------------------------------------------------------IF-----------------------------------------------
--------------------------------------------------------IF-----------------------------------------------
--------------------------------------------------------IF-----------------------------------------------
SELECT * FROM STUDENTTABLE;
CREATE OR REPLACE FUNCTION FINDFLAG(STU_NO IN VARCHAR2) RETURN VARCHAR2 IS
  v_flag VARCHAR2(10);
  v_name STUDENTTABLE.STUDENT_NAME%TYPE;
  
BEGIN
  SELECT STUDENT_NAME INTO v_name FROM  STUDENTTABLE WHERE student_no=STU_NO;
  IF '??'=v_name THEN
    v_flag:=v_name||' 2';
    RETURN v_flag;
  ELSIF '??'=v_name THEN
    v_flag:=v_name||' 3';
    RETURN v_flag;
  ELSE 
    v_flag:='NOT FOUND!!!';
    RETURN v_flag;
  END IF;
END;

--------------------------------------------------------CASE WHEN-----------------------------------------------
--------------------------------------------------------CASE WHEN-----------------------------------------------
--------------------------------------------------------CASE WHEN-----------------------------------------------
--------------------------------------------------------CASE WHEN-----------------------------------------------

CREATE OR REPLACE FUNCTION FINDFLAG2(STU_NO IN VARCHAR2) RETURN VARCHAR2 IS
  v_flag VARCHAR2(10);
  v_name STUDENTTABLE.STUDENT_NAME%TYPE;
  
BEGIN
  SELECT STUDENT_NAME INTO v_name FROM  STUDENTTABLE WHERE student_no=STU_NO;
  CASE
  WHEN  '??'=v_name THEN
    v_flag:=v_name||' 2';
    RETURN v_flag;
  WHEN '??'=v_name THEN
    v_flag:=v_name||' 3';
    RETURN v_flag;
  ELSE  v_flag:='NOT FOUND!!!';
    RETURN v_flag;
  END CASE;
END;

--------------------------------------------------------LOOP-----------------------------------------------
--------------------------------------------------------LOOP-----------------------------------------------
--------------------------------------------------------LOOP-----------------------------------------------
--------------------------------------------------------LOOP-----------------------------------------------
SELECT * FROM STUDENTTABLE;
DECLARE 
  i INT:=1;
BEGIN
  LOOP
    INSERT INTO STUDENTTABLE(STUDENT_NAME) VALUES('STUDENT '|| i);
    EXIT WHEN i=5;
    i:=i+1;
    END LOOP;
    COMMIT;
END;
--------------------------------------------------------WHILE-----------------------------------------------
--------------------------------------------------------WHILE-----------------------------------------------
--------------------------------------------------------WHILE-----------------------------------------------
--------------------------------------------------------WHILE-----------------------------------------------

DECLARE

 i INT:=6;
BEGIN

  WHILE i<10 LOOP
    INSERT INTO STUDENTTABLE(STUDENT_NAME) VALUES('STUDENT '|| i);
    i:=i+1;
  END LOOP;
END;
--------------------------------------------------------FOR-----------------------------------------------
--------------------------------------------------------FOR-----------------------------------------------
--------------------------------------------------------FOR-----------------------------------------------
--------------------------------------------------------FOR-----------------------------------------------
BEGIN

  FOR i IN 10..15 LOOP
    INSERT INTO STUDENTTABLE(STUDENT_NAME) VALUES('STUDENT '|| i);
  END LOOP;
  END;
--------------------------------------------------------EXCEPTION-----------------------------------------------
--------------------------------------------------------EXCEPTION-----------------------------------------------
--------------------------------------------------------EXCEPTION-----------------------------------------------
--------------------------------------------------------EXCEPTION-----------------------------------------------
DECLARE 
  E_INVALID_INPUT EXCEPTION;
  V_STU_NAME studenttable.STUDENT_NAME%TYPE;
  V_STU_NO VARCHAR2(10):=&STU_NO;
BEGIN
    IF V_STU_NO='2' THEN
      RAISE E_INVALID_INPUT;
    END IF;
    SELECT STUDENT_NAME INTO V_STU_NAME FROM studenttable WHERE student_no=V_STU_NO;
    dbms_output.put_line('HELLO, '||V_STU_NAME);
    EXCEPTION 
      WHEN E_INVALID_INPUT THEN
      dbms_output.put_line('INPUT ERROR');
      
END;

--------------------------------------------------------IMPLICIT CURSOR-----------------------------------------------
--------------------------------------------------------IMPLICIT CURSOR-----------------------------------------------
--------------------------------------------------------IMPLICIT CURSOR-----------------------------------------------
--------------------------------------------------------IMPLICIT CURSOR-----------------------------------------------

---SQL%FOUND && SQL%NOTFOUND && SQL%ROWCOUND
DECLARE
  V_STU_NAME studenttable.STUDENT_NAME%TYPE;
  V_ROW_STU studenttable%ROWTYPE;
BEGIN 
  UPDATE studenttable SET STUDENT_NAME='CITI' WHERE student_no=&STU_NO
    RETURNING STUDENT_NAME INTO V_STU_NAME; --USING RETURNING
  IF SQL%FOUND THEN
    dbms_output.put_line('DATA UPDATED, UPDATED ROW COUNT '|| SQL%ROWCOUNT|| ' , NEW NAME IS '|| V_STU_NAME);
  END IF;
  IF SQL%NOTFOUND THEN
    dbms_output.put_line('DATA NOT FOUND...');
  END IF;
  SELECT * INTO V_ROW_STU FROM studenttable WHERE student_NAME=V_STU_NAME;
  dbms_output.put_line('V_ROW_STU ====> '|| V_ROW_STU.student_no||', '|| V_ROW_STU.STUDENT_NAME);
END;
SELECT * FROM STUDENTTABLE;

--USING IMPLICIT CURSOR ,ORACLE WILL EXECUTE OPEN, FETCH,CLOSE .

--BELOW 2 PROCEDURE A ONE EXAMPLE
--BELOW IS TO REMOVE ONE RECORD FROM TABLE
CREATE OR REPLACE PROCEDURE PRO_REMOVE_STU(V_STU_NO IN studenttable.student_no%TYPE)
IS
BEGIN
  DELETE FROM studenttable WHERE STUDENT_NO=V_STU_NO;
END;

--BELOW IS TRY TO QUERY RECORD COUNT, BUT GET FAIL

CREATE OR REPLACE PROCEDURE PRO_QUERY_COUNT1
IS
  V_COUNT INTEGER;
BEGIN
  SELECT COUNT(*) INTO V_COUNT FROM studenttable; --10 RECORDS IN TABLE
  PRO_REMOVE_STU('9999'); --CALL PRO_REMOVE_STU(), BUT 9999 WAS NOT IN DB.
  dbms_output.put_line(SQL%ROWCOUNT ||' RECORDS WAS FOUND IN TABLE'); --WILL PRINT : 0 RECORDS WAS FOUND IN TABLE .BECAUSE SQL%ROWCOUNT WILL ONLY RECORD THE LATEST DML EXECUTION. DUE TO 9999 IS NOT IN DB,SO THE DELETE RETURN 0.
END;

-- TO FIX PRO_QUERY_COUNT1 ISSUE 
CREATE OR REPLACE PROCEDURE PRO_QUERY_COUNT2
IS
  V_COUNT INTEGER;
  V_FOUND_NUM INTEGER;
  V_DELETE_COUNT INTEGER;
BEGIN
  SELECT COUNT(*) INTO V_COUNT FROM studenttable; --1 RECORDS IN TABLE
  V_FOUND_NUM:= SQL%ROWCOUNT;
  PRO_REMOVE_STU('9999'); --CALL PRO_REMOVE_STU(), BUT 9999 WAS NOT IN DB.
  V_DELETE_COUNT:=SQL%ROWCOUNT;
  dbms_output.put_line('TOTAL RECORD NUMBER OF TABLE: '||V_FOUND_NUM || ', REMOVE COUNT NUMBER: '||V_DELETE_COUNT);
END;
 
--------------------------------------------------------EXPLICIT CURSOR-----------------------------------------------
--------------------------------------------------------EXPLICIT CURSOR-----------------------------------------------
--------------------------------------------------------EXPLICIT CURSOR-----------------------------------------------
--------------------------------------------------------EXPLICIT CURSOR-----------------------------------------------

DECLARE 
  CURSOR CUR_STU IS SELECT STUDENT_NO,STUDENT_NAME FROM studenttable;
  V_STU_NO studenttable.STUDENT_NO%TYPE;
  V_STU_NAME studenttable.STUDENT_NAME%TYPE;
BEGIN
  OPEN  CUR_STU;
  LOOP
  FETCH CUR_STU INTO V_STU_NO,V_STU_NAME;
  dbms_output.put_line('STU_NO: '|| V_STU_NO||', STU_NAME: '|| V_STU_NAME);
  EXIT WHEN CUR_STU%NOTFOUND ;
  END LOOP;
  CLOSE CUR_STU;
END;


----use FOR LOOP TO FETCH CURSOR DATA

DECLARE 
  CURSOR CUR_STU IS SELECT STUDENT_NO,STUDENT_NAME FROM studenttable;
BEGIN
  FOR CUR_STU_TEMP IN CUR_STU
  LOOP
    dbms_output.put_line('STU_NO: '|| CUR_STU_TEMP.STUDENT_NO ||', STU_NAME: '|| CUR_STU_TEMP.STUDENT_NAME);
  END LOOP;
   
END;



--------------------------------------------------------TRANSACTION-----------------------------------------------
--------------------------------------------------------TRANSACTION-----------------------------------------------
--------------------------------------------------------TRANSACTION-----------------------------------------------
--------------------------------------------------------TRANSACTION-----------------------------------------------
--COMMIT
--ROLLBACK
--SAVEPOINT
--LOCK TABLE