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Categories / Oracle PLSQL Tutorial / Cursor
 

Checking the status of implicit cursors

You can use the same cursor variables for implicit cursors. The value of a cursor variable corresponds to the last statement needing an implicit cursor. Because there is no cursor name, you use SQL rather than the cursor name. SQL%ROWCOUNT returns row count. SQL%ISOPEN is always false because implicit cursors are opened as needed and closed immediately after the statement is finished. Both SQL%FOUND and SQL%NOTFOUND are false before any statement is executed. Any DDL or transaction control commands (commit or rollback) will clear implicit cursor variables. You can check the value of your cursor variables only prior to doing a commit or rollback. 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> -- 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> begin   2      update employee   3      set salary=salary*1;   4   5      DBMS_OUTPUT.put_line('Processed:'||sql%rowcount);   6   7      if sql%FOUND then   8          DBMS_OUTPUT.put_line('Found=true');   9      else  10          DBMS_OUTPUT.put_line('Found=false');  11      end if;  12  end;  13  / Processed:8 Found=true PL/SQL procedure successfully completed. SQL> SQL> -- clean the table SQL> drop table Employee   2  / Table dropped. SQL>