Rownum in SQL

The Oracle/PLSQL ROWNUM function returns a number that represents the order that a row is selected by Oracle from a table or joined tables.

Example

select * from all_objects where rownum < 2

index Table Type in PLSQL

DECLARE

  TYPE TABLENAMETYPE IS TABLE OF VARCHAR2(30) INDEX BY BINARY_INTEGER;

  L_TABLENAMETYPE TABLENAMETYPE;

BEGIN

  --YOU CAN USE THIS L_TABLENAMETYPE TYPE HERE

  L_TABLENAMETYPE(1) := 'AB';

  L_TABLENAMETYPE(2) := 'ABC';

  L_TABLENAMETYPE(3) := 'ABD';

  L_TABLENAMETYPE(4) := 'ABE';

  FOR LDX IN 1 .. L_TABLENAMETYPE.COUNT

 

   LOOP

 

    DBMS_OUTPUT.PUT_LINE(L_TABLENAMETYPE(LDX));

 

  END LOOP;

  ---DELETE ALL VALUES

  L_TABLENAMETYPE.DELETE;

END;

--RESULT

AB

ABC

ABD

ABE

---USE TABLE TYPE WITH BULK COLLECT INTO

DECLARE

CURSOR C IS

  SELECT * FROM EMP;

TYPE ANY_TABLE_TYPE IS TABLE OF EMP%ROWTYPE INDEX BY BINARY_INTEGER;

EMP_REC ANY_TABLE_TYPE;

BEGIN

  OPEN C;

  FETCH C BULK COLLECT

 

    INTO EMP_REC;

  CLOSE C;

  FORALL I IN EMP_REC.FIRST .. EMP_REC.LAST

 

    UPDATE EMP

   

       SET COMM = EMP_REC(I).SAL * 10 / 100

   

     WHERE EMPNO = EMP_REC(I).EMPNO;

  COMMIT;

END;