Question given relation r (A,B,C,D) and the following fd’s. Identify the candidate key for r and highest normal form b->C, d->a question Consider the universal relation R= {A,



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Implicit cursors

  • Explicit cursors

    Implicit Cursors:

    Implicit cursors are automatically created by Oracle whenever an SQL statement is executed, when there is no explicit cursor for the statement. Programmers cannot control the implicit cursors and the information in it.



    Attributes of implicit cursors:

    • %FOUND

    • %NOTFOUND

    • %ISOPEN

    • %ROWCOUNT

    Explicit Cursors:

    Explicit cursors are programmer-defined cursors for gaining more control over the context area. An explicit cursor should be defined in the declaration section of the PL/SQL Block. It is created on a SELECT Statement which returns more than one row.



    The syntax for creating an explicit cursor is −

    CURSOR cursor_name IS select_statement;
    Working with an explicit cursor includes the following steps −
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