Re: How do they get the answer?

It could be anywhere from 0 to more then 4 teachers receiving increase, depending on whether there are teacher/teachers teaching both subjects, and on whether one (or both subjects) with those IDs (102, 105) exists or not exists in the table.
Extreme case (0 teachers receiving increase), when neither subject_id exists in the table.

Igor Neyman, OCP DBA
Perceptron, Inc.
(734)414-4627
ineyman_at_perceptron.com

• Original Message ----- To: "Multiple recipients of list ORACLE-L" <ORACLE-L_at_fatcity.com> Sent: Tuesday, August 21, 2001 12:57 PM

> I think you're being tricked by the question.
>
> If each subject is taught by two or more teachers, and you're updating the
> salaries of all teachers teaching two subjects, 2 x (2+?) >= 4
>
> Brian
>
> kjanusz_at_att.net wrote:
>
> > I am taking the Self-Test software test for the SQL exam
> > and don't see how they get the answer to this problem.
> > They don't explain how it is arrived at.
> >
> > Any help you can give me will be appreciated.
> >
> > Thanks,
> > Ken Janusz, CPIM
> >
> > ----------------------------------
> >
> > Examine the structure of the TEACHER table:
> >
> > Name Null? Type
> > ID NOT NULL NUMBER(9)
> > SALARY NUMBER
> > (7,2)
> > SUBJECT_ID NOT NULL NUMBER(3)
> > SUBJECT_DESCRIPTION VARCHAR2(2)
> >
> > There are 200 teachers and 15 subjects. Each subject is
> > taught
> > by at least 2 teachers.
> >
> > Evaluate this PL/SQL block:
> >
> > DECLARE
> > v_pct_raise number := 1.10;
> > BEGIN
> > UPDATE teacher
> > SET salary = salary * 1.10
> > WHERE subject_id IN (102, 105);
> > COMMIT;
> > END;
> >
> > Which result will the PL/SQL block provide?
> >
> > (A) Only two teachers will receive a 10% salary increase.
> > (B) All of the teachers will receive a 10% salary
> > increase.
> > (C) At least four teachers will receive a 10% salary
> > increase.
> > (D) A syntax error will occur.
> >
> > Answer:
> > (C)
> >
> > --
> > Please see the official ORACLE-L FAQ: http://www.orafaq.com
> > --
> > Author:
> > INET: kjanusz_at_att.net
> >
> > Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
> > San Diego, California -- Public Internet access / Mailing Lists
> > --------------------------------------------------------------------
> > To REMOVE yourself from this mailing list, send an E-Mail message
> > to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
> > the message BODY, include a line containing: UNSUB ORACLE-L
> > (or the name of mailing list you want to be removed from). You may
> > also send the HELP command for other information (like subscribing).
>
> --
> --------------------------------------
> | Brian McGraw -- Oracle DBA |
> | Central Alabama Oracle Users Group |
> |------------------------------------|
> | mailto:BMcGraw_at_mindspring.com |
> | http://bmcgraw.home.mindspring.com |
> --------------------------------------
>
>
> --
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> --
> Author: Brian McGraw
> INET: brian.mcgraw_at_infinity-insurance.com
>
> Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
> San Diego, California -- Public Internet access / Mailing Lists
> --------------------------------------------------------------------
> To REMOVE yourself from this mailing list, send an E-Mail message
> to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
> the message BODY, include a line containing: UNSUB ORACLE-L
> (or the name of mailing list you want to be removed from). You may
> also send the HELP command for other information (like subscribing).

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: Igor Neyman
  INET: ineyman_at_perceptron.com

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).