Re: relational reasoning -- why two tables and not one?
From: paul c <toledobythesea_at_oohay.ac>
Date: Fri, 16 Oct 2009 03:17:39 GMT
Message-ID: <nBRBm.48241$Db2.7044_at_edtnps83>
>
> SAP foregoes any and all dbms constraint checking. It implements its own
> flavor of SQL that gets translated to the underlying dbms. Views? Bwa ha
> ha ha ha... let me regain my composure. No, they don't use views, and
> anything that even remotely smells like database access goes through
> some function call or another. Updates generally get queued in some sort
> of unindexed or lightly indexed table where inserts are fast and then
> processed after the fact. SAP very heavily overloads tables and the
> side-effects can be staggering.
Date: Fri, 16 Oct 2009 03:17:39 GMT
Message-ID: <nBRBm.48241$Db2.7044_at_edtnps83>
Bob Badour wrote:
> paul c wrote:
>
>> Clifford Heath wrote: >> >>> paul c wrote: >>> ... >>> I hope the SAP example shows that's simply not the case. 500 tables is >>> considered to be medium-sized in my experience. >>> >>> Last year I used CQL to model motor vehicle insurance claims. The model >>> had 100 nouns, though the database was only 18 tables. It did not >>> include >>> most of the complexity of motor vehicle insurance, did not model the >>> policy, >>> underwriting, insurance history, nor many other facets; and this >>> organisation >>> handled more than twenty other types of insurance. >> >> Thanks for that prompt, SAP was one of the products I had in mind. >> I'm very curious to what extent SAP uses views. I gather that it runs >> on SQL server, Oracle and perhaps other dbms'. Does it use some >> subterfuge to update/insert/delete to/from views? Does it implement >> its own integrity mechanisms to get around the various inadequacies of >> those dbms'?
>
> SAP foregoes any and all dbms constraint checking. It implements its own
> flavor of SQL that gets translated to the underlying dbms. Views? Bwa ha
> ha ha ha... let me regain my composure. No, they don't use views, and
> anything that even remotely smells like database access goes through
> some function call or another. Updates generally get queued in some sort
> of unindexed or lightly indexed table where inserts are fast and then
> processed after the fact. SAP very heavily overloads tables and the
> side-effects can be staggering.
Interesting, I have to conclude that any buyer who thinks it has something to do with relational doesnèt know what heès buying, let along doing. Received on Fri Oct 16 2009 - 05:17:39 CEST