> > Wouldn't disjunctive normal form be better, since it can be
> implemented as
> > the simple union of a set of small queries?
>
> Please tell us more.

Well, I don't know how the backend processes queries, but one can imagine
this scenario (for DNF):

1) Analyze query and set up columns in result table
2) Rewrite query into DNF
3) Split query into subqueries
4) For each subquery:
  a) Process query
  b) Append matching tuples to result table
5) Do any post-processing (ORDER BY, etc.)
6) Return result

How is the processing currently done (with CNF)?

Taral

In response to

• Re: [GENERAL] Long update query ? at 1998-10-01 22:54:19 from Bruce Momjian

Responses

• Re: [GENERAL] Long update query ? (also Re: [GENERAL] CNF vs. DNF) at 1998-10-02 02:18:29 from Bruce Momjian

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