What are the cursor attributes used in PL/SQL?

For Implicit Cursors:-
Found - Returns TRUE If the last DML Statement affect atleast 1 row otherwise FALSE.
NotFound - Returns TRUE If last DML Statement doesn't affect atleast 1 row otherwise FALSE.
Rowcount - Returns number of rows affected by the last DML statement.
Isopen - Returns TRUE if the cursor is open otherwise FALSE. Its always returns FALSE incase of implicit cursor. Because after executing the DML statement Oracle Server automatically close the cursor.

For Explicit Cursors:-
Found - Returns TRUE if the Last fetch returns a Row otherwise FALSE.
NotFound - Returns TRUE if the last fetch doesn't return any row otherwise FALSE.
Rowcount - Returns number of rows returned so far from the active set.
Isopen - Returns TRUE if the cursor is open otherwise FALSE.

What is a cursor ? Why Cursor is required ?

CURSOR
Whenever a sql statement is issued at that time oracle server will allocate some memory area to execute and parse that sql statement. That data area is called as cursor.

Two types : IMPLICIT EXPLICIT


IMPLICIT
-----------
(1) Called as SQL.
(2) Never user CURSOR keyword explicitly
(3) Memory allocation and program controll will done automatically
(4) Returns or updates or deletes only one record.
(5) Attributes : SQL FOUND SQL NOTFOUND

EXPLICIT
-----------
(1) called as cursors
(2) Uses CURSOR keyword explicitly
(3) Memory allocation and program control thru the cursor written.
(4) Returns or updates or deletes multiple records.
(5) Attributes : SQL FOUND SQL NOTFOUND ISOPEN ROWCOUNT

What is PL/SQL table ?

A PL/SQL table is a one-dimensional, unbounded, sparse collection of homogenous elements, indexed by integers

One-dimensional

A PL/SQL table can have only one column. It is, in this way, similar to a one-dimensional array. 

Unbounded or Unconstrained

There is no predefined limit to the number of rows in a PL/SQL table. The PL/SQL table grows dynamically as you add more rows to the table. The PL/SQL table is, in this way, very different from an array.

Related to this definition, no rows for PL/SQL tables are allocated for this structure when it is defined. 

Sparse

In a PL/SQL table, a row exists in the table only when a value is assigned to that row. Rows do not have to be defined sequentially. Instead you can assign a value to any row in the table. So row 15 could have a value of `Fox' and row 15446 a value of `Red', with no other rows defined in between. 

Homogeneous elements

Because a PL/SQL table can have only a single column, all rows in a PL/SQL table contain values of the same datatype. It is, therefore, homogeneous.

With PL/SQL Release 2.3, you can have PL/SQL tables of records. The resulting table is still, however, homogeneous. Each row simply contains the same set of columns. 

Indexed by integers

PL/SQL tables currently support a single indexing mode: by BINARY_INTEGER. This number acts as the "primary key" of the PL/SQL table. The range of a BINARY_INTEGER is from -2³¹-1 to 2³¹-1, so you have an awful lot of rows with which to work