Re: Fw: Is SQL silly as an RDBMS<->app interface?
От | Vincent Hikida |
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Тема | Re: Fw: Is SQL silly as an RDBMS<->app interface? |
Дата | |
Msg-id | 027401c35249$8c21a010$210110ac@HOMEOFFICE обсуждение исходный текст |
Ответ на | Re: Fw: Is SQL silly as an RDBMS<->app interface? (Bruce Momjian <pgman@candle.pha.pa.us>) |
Ответы |
Re: Fw: Is SQL silly as an RDBMS<->app interface?
Re: Fw: Is SQL silly as an RDBMS<->app interface? |
Список | pgsql-general |
----- Original Message ----- From: "Bruce Momjian" <pgman@candle.pha.pa.us> To: "elein" <elein@varlena.com> Cc: "Jan Wieck" <JanWieck@Yahoo.com>; "Vincent Hikida" <vhikida@inreach.com>; <pgsql-general@postgresql.org> Sent: Thursday, July 24, 2003 5:35 PM Subject: Re: Fw: [GENERAL] Is SQL silly as an RDBMS<->app interface? > > Yes, it was more powerful because you could do aggregates in the query > independent of the results returned by the query. > > The 'by' feature of aggregates always confused me because it would > modify the aggregate WHERE clause (that was independent of the outer > query) and restrict the aggregate to only process rows where the outer > query's column value matched the same column's value in the aggregate. > Actually, I used a hierarchical/relational DBMS called Nomad in 1981. If I understand Bruce, Nomad could do the same thing. I could aggregate at different levels in the same query. Each aggregate created a break and I could add whatever code I wanted at the level. I could also refer to any level of aggregate in the rest of the query. I could also refer to any level aggregate in the rest of the code. This meant that I could for example calculate what percentage of the total the individual row was. The only problem was that I could only join two tables at a time so if I wanted to join several tables I had to have several statements. Each statement created an intermediate table which was easy to refer to in subsequent statements. Vincent
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