> On Saturday 30 August 2008 5:23:25 am Albretch Mueller wrote:
> > On Thu, Aug 28, 2008 at 7:50 PM, Adrian Klaver <aklaver@comcast.net>
wrote:
> > > Define easily.
> >
> > ~
> > OK, let me try to outline the approach I would go for:
> > ~
> > I think "COPY FROM CSV" should have three options, namely:
> > ~
> > 1) the way we have used it in which you create the table first
> > ~
> > 2) another way in which defaults are declared, generally as:
> > ~
> > 2.1) aggressive: data type, value and formatting analysis is done; if
> > only 1 or 0 are found declare then a BOOLEAN, if repeated data is
> > found (say state codes) and the stratification nodes cover the rest of
> > the data, stratify the data out to other extra table (they have a name
> > I can't recall now), index it ..., if data is kind of numeric with
> > front slashes and/or hyphen could they possibly be dates? if they are
> > definitelly dates convert them to bigint (and do the formatting in the
> > presentation code (also this a win-win situation with i18n code)) ...
> > ~
> > 2.2) conservative: data type and value, but no formatting analysis is
> > done and the greater encompassing data type is selected, say for 1 or
> > 0 data use bytes [0, 255], for bytes use int, if something could be
> > encoded as char(2), use varchar instead, . . .
> > ~
> > 2.3) dumn: just use the coarsest data type possible; bigint for
> > anything that looks like a number and varchar for the rest
> > ~
> > the "dumn" option should suggest to the DBA the option they are
> > using, quantified consequences for their desicions (larger DBs for no
> > reason, approx. reduction in speed, . .) and how not to be "dumn"
> > ~
> > 3) or you could define "import templates" declaring which specific
> > data types to use for data in a certain way, which could be declared
> > per column using regexps
> > ~
> >
> > > I could go on, but the point is that table data types require some
> > > thought on the part of the DBA.
> >
> > ~
> > Well, it still requires their minds and input, but they will have
> > jobs even if they get some help, don't you think so ;-)
> > ~
> > lbrtchx
>
> This is a combination of more work then necessary and putting the cart
> after the horse. All I can see happening is delaying the point of decision
Lets try this again. The cart before the horse.
Memo to self:
1) Drink sufficient coffee.
2) Answer email.
> to a later time and or dumping the decision process on someone else. There
> is already a "dumb" solution that has been brought many times on this list.
> It involve creating a holding table that has text only fields and copying
> the data into and then moving the data from there to a final table. As far
> as import templates I suggest looking at:
> http://pgloader.projects.postgresql.org/
> It also addresses some of your other suggestions. It does not automatically
> create a table though.
>
>
>
> --
> Adrian Klaver
> aklaver@comcast.net
--
Adrian Klaver
aklaver@comcast.net
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