Oracle PL/SQL/Cursor/Implicit Cursor — различия между версиями

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Текущая версия на 09:54, 26 мая 2010

Cursor for loop

  
SQL>
SQL> CREATE TABLE departments
  2  (department_id           number(10)            not null,
  3   department_name      varchar2(50)      not null,
  4   CONSTRAINT departments_pk PRIMARY KEY (department_id)
  5  );
Table created.
SQL>
SQL>
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 1,             "Data Group" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 2,             "Purchasing" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 3,             "Call Center" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 4,             "Communication" );
1 row created.
SQL>
SQL>
SQL>  set serverout on
SQL>
SQL>  declare
  2    begin
  3      for my_dept_rec in (select department_id, department_name
  4                            from departments
  5                           order by 1)
  6      loop
  7        dbms_output.put("Department #" || my_dept_rec.department_id);
  8        dbms_output.put_line(" is named " || my_dept_rec.department_name);
  9      end loop;
 10    end;
 11    /
Department #1 is named Data Group
Department #2 is named Purchasing
Department #3 is named Call Center
Department #4 is named Communication
PL/SQL procedure successfully completed.
SQL>
SQL> drop table departments;
Table dropped.
SQL>



explicit cursor with cursor variable

  
SQL>
SQL> create table myTable (x primary key) organization index as select 1 from dual;
Table created.
SQL>
SQL>
SQL>
SQL>
SQL> create or replace procedure explicit is
  2    cursor explicit_cur is select 1 from myTable;
  3    dummy number;
  4  begin
  5    for i in 1 .. 500 loop
  6       open explicit_cur;
  7       fetch explicit_cur
  8       into dummy;
  9       close explicit_cur;
 10    end loop;
 11  end;
 12  /
Procedure created.
SQL>
SQL>
SQL> drop table myTable;
Table dropped.



for data in ( select * from tableName )

  
SQL>
SQL>
SQL> CREATE TABLE DEPT(
  2      DEPTNO NUMBER(2),
  3      DNAME VARCHAR2(14),
  4      LOC VARCHAR2(13)
  5  );
Table created.
SQL>
SQL> INSERT INTO DEPT VALUES (10, "ACCOUNTING", "NEW YORK");
1 row created.
SQL> INSERT INTO DEPT VALUES (20, "RESEARCH", "DALLAS");
1 row created.
SQL> INSERT INTO DEPT VALUES (30, "SALES", "CHICAGO");
1 row created.
SQL> INSERT INTO DEPT VALUES (40, "OPERATIONS", "BOSTON");
1 row created.
SQL>
SQL>
SQL> create or replace procedure implicit
  2  as
  3  begin
  4      for x in ( select * from dept )
  5      loop
  6          null;
  7      end loop;
  8  end;
  9  /
Procedure created.
SQL>
SQL>
SQL> drop table dept;
Table dropped.
SQL>
SQL>
SQL>



Implicit cursor by for loop

  
SQL> create table myTable (x primary key) organization index as select 1 from dual;
Table created.
SQL>
SQL>
SQL> create or replace procedure implicit is
  2    dummy number;
  3  begin
  4    for i in 1 .. 500 loop
  5       select 1 into dummy from myTable;
  6    end loop;
  7  end;
  8  /
Procedure created.
SQL>
SQL>
SQL>
SQL> drop table myTable;
Table dropped.



Implicit cursors: SQL%FOUND returns TRUE if SQL statement found one or more records

 

SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL,
  3    First_Name         VARCHAR2(10 BYTE),
  4    Last_Name          VARCHAR2(10 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(10 BYTE),
  9    Description        VARCHAR2(15 BYTE)
 10  )
 11  /
Table created.
SQL>
SQL> -- prepare data
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2               values ("01","Jason",    "Martin",  to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto",  "Programmer")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("02","Alison",   "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("03","James",    "Smith",   to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("04","Celia",    "Rice",    to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("05","Robert",   "Black",   to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("06","Linda",    "Green",   to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York",  "Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("07","David",    "Larry",   to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York",  "Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("08","James",    "Cat",     to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
Hit a key to continue
ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL> -- Implicit cursors:  SQL%FOUND returns TRUE if SQL statement found one or more records.
SQL>
SQL> BEGIN
  2     UPDATE employee
  3        SET salary = salary *2
  4     WHERE id = "01";
  5
  6  IF SQL%FOUND THEN
  7       DBMS_OUTPUT.PUT_LINE("Rows updated.");
  8     END IF;
  9  END;
 10  /
Rows updated.
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>
SQL>



Implicit Cursors: sql%rowcount

  
SQL>
SQL> CREATE TABLE departments
  2  (department_id           number(10)            not null,
  3   department_name      varchar2(50)      not null,
  4   CONSTRAINT departments_pk PRIMARY KEY (department_id)
  5  );
Table created.
SQL>
SQL>
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 1,             "Data Group" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 2,             "Purchasing" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 3,             "Call Center" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 4,             "Communication" );
1 row created.
SQL>
SQL> declare
  2  begin
  3    update departments
  4       set department_name = department_name
  5     where 1 = 2;
  6
  7    dbms_output.put ("An update with a WHERE clause 1 = 2 effects ");
  8    dbms_output.put_line(sql%rowcount || " records.");
  9
 10    update departments
 11       set department_name = department_name;
 12
 13    dbms_output.put("No WHERE clause in an update effects ");
 14    dbms_output.put_line(sql%rowcount || " records.");
 15  end;
 16  /
An update with a WHERE clause 1 = 2 effects 0 records.
No WHERE clause in an update effects 4 records.
PL/SQL procedure successfully completed.
SQL>
SQL> drop table departments;
Table dropped.
SQL> --



Reference implicit in insert statement

  
SQL> CREATE TABLE lecturer (
  2    id               NUMBER(5) PRIMARY KEY,
  3    first_name       VARCHAR2(20),
  4    last_name        VARCHAR2(20),
  5    major            VARCHAR2(30),
  6    current_credits  NUMBER(3)
  7    );
Table created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10001, "Scott", "Lawson","Computer Science", 11);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major, current_credits)
  2                VALUES (10002, "Mar", "Wells","History", 4);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10003, "Jone", "Bliss","Computer Science", 8);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10004, "Man", "Kyte","Economics", 8);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10005, "Pat", "Poll","History", 4);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10006, "Tim", "Viper","History", 4);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10007, "Barbara", "Blues","Economics", 7);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10008, "David", "Large","Music", 4);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10009, "Chris", "Elegant","Nutrition", 8);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10010, "Rose", "Bond","Music", 7);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10011, "Rita", "Johnson","Nutrition", 8);
1 row created.
SQL>
SQL> INSERT INTO lecturer (id, first_name, last_name, major,current_credits)
  2                VALUES (10012, "Sharon", "Clear","Computer Science", 3);
1 row created.
SQL>
SQL> CREATE TABLE myStudent (
  2    student_id NUMBER(5) NOT NULL,
  3    department CHAR(3)   NOT NULL,
  4    course     NUMBER(3) NOT NULL,
  5    grade      CHAR(1)
  6    );
Table created.
SQL>
SQL>
SQL>
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10000, "CS", 102, "A");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10002, "CS", 102, "B");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10003, "CS", 102, "C");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10000, "HIS", 101, "A");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10001, "HIS", 101, "B");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10002, "HIS", 101, "B");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10003, "HIS", 101, "A");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10004, "HIS", 101, "C");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10005, "HIS", 101, "C");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10006, "HIS", 101, "E");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10007, "HIS", 101, "B");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10008, "HIS", 101, "A");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10009, "HIS", 101, "D");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10010, "HIS", 101, "A");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10008, "NUT", 307, "A");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10010, "NUT", 307, "A");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10009, "MUS", 410, "B");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10006, "MUS", 410, "E");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10011, "MUS", 410, "B");
1 row created.
SQL>
SQL> INSERT INTO myStudent (student_id, department, course, grade)
  2                           VALUES (10000, "MUS", 410, "B");
1 row created.
SQL>
SQL>
SQL> CREATE TABLE MyTable (
  2    num_col    NUMBER,
  3    char_col   VARCHAR2(60)
  4    );
Table created.
SQL>
SQL> BEGIN
  2    FOR myLecturer IN (SELECT id, first_name, last_name
  3                            FROM lecturer
  4                            WHERE major = "History") LOOP
  5      INSERT INTO myStudent (student_id, department, course)
  6        VALUES (myLecturer.ID, "HIS", 301);
  7
  8      INSERT INTO MyTable (num_col, char_col)
  9        VALUES (myLecturer.ID,
 10                myLecturer.first_name || " " || myLecturer.last_name);
 11    END LOOP;
 12  END;
 13  /
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL> select * from MyTable;
 NUM_COL CHAR_COL
-------- ------------------------------------------------------------
######## Mar Wells
######## Pat Poll
######## Tim Viper
SQL>
SQL> drop table MyTable;
Table dropped.
SQL>
SQL> drop table lecturer;
Table dropped.
SQL>
SQL> drop table myStudent;
Table dropped.



Test cursor attributes with an implicit cursor

  
SQL>
SQL> CREATE TABLE book (
  2    isbn      CHAR(10) PRIMARY KEY,
  3    category  VARCHAR2(20),
  4    title     VARCHAR2(100),
  5    num_pages NUMBER,
  6    price     NUMBER,
  7    copyright NUMBER(4),
  8    emp1   NUMBER,
  9    emp2   NUMBER,
 10    emp3   NUMBER
 11  );
Table created.
SQL>
SQL> INSERT INTO book (isbn, category, title, num_pages, price, copyright, emp1, emp2, emp3)
  2             VALUES ("1", "Database", "Oracle", 563, 39.99, 2009, 1, 2, 3);
1 row created.
SQL> INSERT INTO book (isbn, category, title, num_pages, price, copyright, emp1, emp2)
  2             VALUES ("2", "Database", "MySQL", 765, 44.99, 2009, 4, 5);
1 row created.
SQL> INSERT INTO book (isbn, category, title, num_pages, price, copyright, emp1, emp2, emp3)
  2             VALUES ("3", "Database", "SQL Server", 404, 39.99, 2001, 6, 7, 8);
1 row created.
SQL>
SQL> SET SERVEROUTPUT ON ESCAPE OFF
SQL>
SQL>
SQL> BEGIN
  2     DBMS_OUTPUT.ENABLE(1000000);
  3     UPDATE book SET price = price * .90 WHERE isbn = "1";
  4
  5     DBMS_OUTPUT.PUT_LINE(SQL%ROWCOUNT||" rows updated");
  6
  7     IF SQL%NOTFOUND
  8     THEN
  9        DBMS_OUTPUT.PUT_LINE("Unable to update isbn 1");
 10     END IF;
 11
 12     COMMIT;
 13
 14  EXCEPTION
 15     WHEN OTHERS
 16        THEN
 17        DBMS_OUTPUT.PUT_LINE(SQLERRM);
 18  END;
 19  /
1 rows updated
PL/SQL procedure successfully completed.
SQL>
SQL> drop table book;
Table dropped.



use cursor attributes on the implicit SQL cursor.

  
SQL>
SQL>
SQL> CREATE TABLE place (
  2    room_id          NUMBER(5) PRIMARY KEY,
  3    building         VARCHAR2(15),
  4    room_number      NUMBER(4),
  5    number_seats     NUMBER(4),
  6    description      VARCHAR2(50)
  7    );
Table created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats, description)
  2             VALUES (20001, "Building 7", 201, 1000, "Large Lecture Hall");
1 row created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats, description)
  2             VALUES (20002, "Building 6", 101, 500, "Small Lecture Hall");
1 row created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats, description)
  2             VALUES (20003, "Building 6", 150, 50, "Discussion Room A");
1 row created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats, description)
  2             VALUES (20004, "Building 6", 160, 50, "Discussion Room B");
1 row created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats,description)
  2             VALUES (20005, "Building 6", 170, 50, "Discussion Room C");
1 row created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats, description)
  2             VALUES (20006, "Music Building", 100, 10, "Music Practice Room");
1 row created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats, description)
  2             VALUES (20007, "Music Building", 200, 1000, "Concert Room");
1 row created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats, description)
  2             VALUES (20008, "Building 7", 300, 75, "Discussion Room D");
1 row created.
SQL>
SQL> INSERT INTO place (room_id, building, room_number, number_seats,description)
  2             VALUES (20009, "Building 7", 310, 50, "Discussion Room E");
1 row created.
SQL>
SQL> BEGIN
  2    UPDATE place
  3      SET number_seats = 100
  4      WHERE room_id = 99980;
  5    IF SQL%NOTFOUND THEN
  6      INSERT INTO place (room_id, number_seats)
  7        VALUES (99980, 100);
  8    END IF;
  9  END;
 10  /
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL> drop table place;
Table dropped.
SQL>



use for loop cursor

  
SQL>
SQL> CREATE TABLE departments
  2  (department_id           number(10)            not null,
  3   department_name      varchar2(50)      not null,
  4   CONSTRAINT departments_pk PRIMARY KEY (department_id)
  5  );
Table created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 1,             "Data Group" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 2,             "Purchasing" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 3,             "Call Center" );
1 row created.
SQL>
SQL> insert into departments ( department_id, department_name )
  2                    values( 4,             "Communication" );
1 row created.
SQL>
SQL> set serveroutput on
SQL> declare
  2  begin
  3    for my_dept_rec in (select department_id, department_name from departments order by 1)
  4    loop
  5      dbms_output.put("Department #" || my_dept_rec.department_id);
  6      dbms_output.put_line(" is named " || my_dept_rec.department_name);
  7    end loop;
  8  end;
  9  /
Department #1 is named Data Group
Department #2 is named Purchasing
Department #3 is named Call Center
Department #4 is named Communication
PL/SQL procedure successfully completed.
SQL>
SQL> DROP TABLE departments;
Table dropped.
SQL> --



Use implicit cursor

 
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL,
  3    First_Name         VARCHAR2(10 BYTE),
  4    Last_Name          VARCHAR2(10 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(10 BYTE),
  9    Description        VARCHAR2(15 BYTE)
 10  )
 11  /
Table created.
SQL>
SQL> -- prepare data
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2               values ("01","Jason",    "Martin",  to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto",  "Programmer")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("02","Alison",   "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("03","James",    "Smith",   to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("04","Celia",    "Rice",    to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("05","Robert",   "Black",   to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("06","Linda",    "Green",   to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York",  "Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("07","David",    "Larry",   to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York",  "Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("08","James",    "Cat",     to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /
ID   FIRST_NAME LAST_NAME  START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- ---------- ---------- --------- --------- ---------- ---------- ---------------
01   Jason      Martin     25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison     Mathews    21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James      Smith      12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia      Rice       24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert     Black      15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda      Green      30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David      Larry      31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James      Cat        17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL> set serverout on;
SQL>
SQL> -- implicit cursor
SQL>
SQL>  declare
  2    begin
  3      update employee set first_name = last_name where 1 = 2;
  4
  5      dbms_output.put ("An update with a WHERE clause 1 = 2 effects ");
  6      dbms_output.put_line(sql%rowcount || " records.");
  7
  8      update employee  set first_name = last_name;
  9
 10      dbms_output.put("No WHERE clause in an update effects ");
 11      dbms_output.put_line(sql%rowcount || " records.");
 12    end;
 13    /
An update with a WHERE clause 1 = 2 effects 0 records.
No WHERE clause in an update effects 8 records.
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL>
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.
SQL>
SQL>



Use implicit or explicit cursor to insert 50000 rows to a table

  
SQL> create table myTable ( x primary key )
  2   organization index as select 1 from dual;
Table created.
SQL> create or replace procedure implicit is
  2   dummy number;
  3  begin
  4   for i in 1 .. 50000 loop
  5       select 1 into dummy from myTable;
  6   end loop;
  7  end;
  8  /
Procedure created.
SQL> create or replace procedure explicit is
  2   cursor explicit_cur is select 1 from myTable;
  3   dummy number;
  4  begin
  5   for i in 1 .. 50000 loop
  6       open explicit_cur;
  7       fetch explicit_cur into dummy;
  8       close explicit_cur;
  9   end loop;
 10  end;
 11  /
Procedure created.
SQL>
SQL> drop table myTable;
Table dropped.



Use passed in value with creating a cursor

  
SQL> CREATE TABLE products(
  2    product_id              NUMBER(6),
  3    name            VARCHAR2(50),
  4    price      NUMBER(8,2),
  5    min_price       NUMBER(8,2)
  6  );
Table created.
SQL>
SQL> create or replace function GetProductTaxIn (in_product_id number) return number
  2  is
  3          priceValue number;
  4          cursor dataCursor is select nvl(round(price * 1.15,2),0) from products where product_id = in_product_id;
  5  begin
  6            open dataCursor;
  7            fetch dataCursor into priceValue;
  8            return priceValue;
  9  exception
 10         when others then priceValue := 0;
 11         return priceValue;
 12  end;
 13  /
Function created.
SQL>
SQL>
SQL>
SQL> select product_id, price, GetProductTaxIn(product_id)
  2    from products
  3   where GetProductTaxIn(product_id)>= 500
  4
SQL>
SQL> drop table products;
Table dropped.
SQL>
SQL>



Write an implicit cursor in a FOR loop and use the data

  
SQL> BEGIN
  2    FOR i IN (SELECT item_title FROM item) LOOP
  3      dbms_output.put_line("The title is ["||i.item_title||"]");
  4    END LOOP;
  5  END;
  6  /
SQL>