Thanks so much for your help. I'm very new to the world of SQL/Oracle, so
Im still trying to get a handle on this stuff. Im creating my tables with
SQL Plus.
Now I know the right direction I should be looking towards. Triggers and
Procedures. Thanks so much.
"Mark C. Stock" <mcstockX_at_Xenquery .com> wrote in message
news:N7-dneJE4MTsq9bcRVn-gg_at_comcast.com...
>
> "sali" <skhan_at_mdsp.org> wrote in message
> news:TqG2d.9$Ov3.1217_at_news.abs.net...
> | I have this table called Faculty_Schedule, which contains a faculty
> member's
> | schedule for a particular semester. In the creation of the table, I
need
> to
> | add a check constraint where the teacher can not teach more than 4
classes
> | per semester. Here is what i have so far.
> |
> | CREATE TABLE faculty_schedule(
> | fac_schedule_id NUMBER(2),
> | faculty_semster VARCHAR(6),
> | faculty_id NUMBER(5),
> | course_id NUMBER(5),
> | CONSTRAINT fac_sch_id_pk PRIMARY KEY (fac_schedule_id),
> | CONSTRAINT course_id_fk FOREIGN KEY (course_id) REFERENCES courses
> | (course_id),
> | CONSTRAINT faculty_id_fk FOREIGN KEY (faculty_id) REFERENCES faculty
> | (faculty_id));
> |
> | How would I include this CHECK constraint in here. This is the first
time
> | im writing something that has this type of constraint so I am a little
> | confused about the way it should be done.. Any help would be
appreciated.
> | Thanks in advance.
> |
> |
>
> no can do -- CHECK constraints can't reference other rows, which is what
you
> need to do to find out how many classes the teacher has
>
> this will likely need to be done with a procedure or with triggers (but
> limitations on triggers make this a bit tricky)
>
> what's your development environment? if you can encapsulate your SQL in a
> stored procedure then you can perform the check in the procedure before or
> after the DML on your schedule table and at the end of the transaction
>
> ++ mcs
>
>
Received on Fri Sep 17 2004 - 14:22:25 CDT
