Re: Diff. between v6 & 7??

Bob Blizard (rblizard_at_bb.cmcsys.com) wrote:
: In article <199503312007.OAA17469_at_dlep1.itg.ti.com> sinh_at_dlep1.itg.ti.com (Arun Sinha) writes:

[Snip]
: >Can some one tell me the major differences between versions 6 & 7.
[Snip]

: 1. True referential integrity. In O6 you can declare foreign keys, but they
: are not enforced. In O7, foreign keys are enforced. This means a big
: improvement in data integrity; no more child rows without parents or lookup
: ids without lookups to look for.
 

: 2. Stored procedures and triggers. This is a huge difference. Now you can do
: processing in your server for stuff that belongs there. For instance, use a
: trigger to verify that the person making the change to the salary is
: authorized for the amount of the change. Use one to automatically put a
: timestamp and user initials into audit column of a table on every insert or
: update. Stored procedures can do anything that PL/SQL can do, but do without
: having to pass the code to the server each time. Starting in 7.1 (I think) you
: can use stored code to create your own functions, and call them just as you
: would SQL functions.
 

: 3. Roles. A role is a collection of system and table permissions, assigned to
: an object instead of a user. You can create the 'Bookkeeper' role, assign it
: the permissions it requires, and then grant the role to any user who is a
: bookkeeper. Roles are additive - assign several and the permissions will be
: the highest common denominator.
 

: 4. Cost-Based Query Optimizer. If they get it to work correctly, it will be a
: great thing. Potentially better than a rule-based optimizer.
 

: 5. SGA is more dynamic. Sort area spaces drop back in size when unused.
: Rollback segs also can be set up to drop back to an assigned 'optimal' size
: when they are no longer in use.
 

: That's a start. Let's see what else others have to say...

6. Shared Context Area. If many people execute the same (identical) SQL statement, the parsing and optimisation happens once, and the resultant execution plan is held in the SGA. This also applies to PL/SQL blocks such as stored procedures and triggers. (From memory, so open to correction).

--
Mark Bluemel	Unix/Oracle Trainer and Consultant
		My opinions are my own, but I'll share them
		All solutions to problems are offered "as is"
		and without warranty - you have been warned :-)