Basic Oracle Concepts and Programming Question: Download Oracle Database PDF

Answer #1The implicit cursor is the cursor automatically defined by PL/SQL for you. Whenever a SQL statement is executed, this cursor will be assigned to represent the execution of this statement. This implicit cursor is called SQL. It has many attributes representing some good information about the execution like:

► SQL%FOUND - True, if the SQL statement has changed any rows.
► SQL%NOTFOUND - True, if the SQL statement has not changed any rows.
► SQL%ROWCOUNT - The number of rows affected by the SQL statement.

See the example below on how to use the implicit cursor:

CREATE TABLE student (id NUMBER(5) PRIMARY KEY,
first_name VARCHAR(80) NOT NULL,
last_name VARCHAR(80) NOT NULL);
Table created.

Answer #2<pre>DECLARE
id NUMBER;
first_name CHAR(10);
BEGIN
id := 29;
first_name := 'Bob';
INSERT INTO student VALUES(id, first_name, 'Henry');
first_name := 'Joe';
INSERT INTO student VALUES(id+1, first_name, 'Bush');

first_name := 'ggl';
UPDATE student SET first_name = first_name WHERE id = 29;
IF SQL%FOUND THEN
DBMS_OUTPUT.PUT_LINE('# of rows updated: ' ||
SQL%ROWCOUNT);
END IF;

UPDATE student SET first_name = first_name
WHERE id = id+1;
IF SQL%NOTFOUND THEN
DBMS_OUTPUT.PUT_LINE('No records updated.');
END IF;

DELETE FROM student WHERE id = id;
DBMS_OUTPUT.PUT_LINE('# of rows updated: ' ||
SQL%ROWCOUNT);
END;
/</pre>
# of rows updated: 1
No records updated.
# of rows updated: 2