Types of Cursors

Types of Cursors:
There are two types of cursors

• Implicit cursors
• Explicit cursors

Implicit cursors:

• It is a CURSOR that is automatically declared by oracle every time an SQL statement is executed.
• These are created or erased automatically.
• These are identified by SQL%<cursor attribute>
• Whenever you issue a SQL statement, the Oracle server opens an area of memory in which the command is parsed and executed. This area is called a cursor.
• When the executable part of a block issues a SQL statement, PL/SQL creates an implicit cursor, which PL/SQL managers automatically.
• A CURSOR is automatically associated with every DML statement.
• All UPDATE and DELETE statements have cursors that identify the set of rows that will be affected by the operations.
• During processing of an IMPLICIT cursor, oracle automatically performs the operations like “OPEN”,”FETCH”, and “CLOSE” of the context area.

Explicit Cursor:

• Explicit cursors are explicitly declared by the programmer.
• This cursor is declared within the PL/SQL block, and allows sequential process of each row of the returned data from database.