Re: [SQL] [HACKERS] Our FLOAT(p) precision does not conform to spec

2003-06-18 Thread Shridhar Daithankar
On 16 Jun 2003 at 18:15, Tom Lane wrote:
> This is a straightforward change and would not break pg_dump files,
> since fortunately pg_dump always references the underlying types and
> never refers to anything as FLOAT(p).  But I wonder whether it is
> likely to break many existing applications.  There is a hazard of some
> existing app asking for (what it thinks is) float8 and getting float4
> instead.

Especially apps. which rely on number(3) not to accept anything greate than +/-
999.

I hate the syntax of putting decimal digits as range checkers in SQL field. But 
oracle does that and consequently lot of oracle apps rely on it. I won't be 
surprised if float(p) notion brings same assurance to such app developers.

I think this would become and FAQ after changes are implemented. Who reads 
release notes anyway?..:-)
 
> Is it worth trying to provide some sort of backwards-compatibility mode?
> We could imagine adding a GUC variable to select binary or decimal
> precision, but I really don't want to.  It would increase the amount of
> work needed by more than an order of magnitude, and this problem doesn't
> seem worth it.  I'd rather just list this under Incompatibilities in the
> 7.4 release notes.

Is it possible to have float-2(p) and float-10(p)? Would it be adding code 
sections instead of replacing it?

That would be cleaner than GUC variable. Everything defaults to float-10(p) for 
backward compatibility for a period of a release and in 7.5, it gets switched 
to float-2(p). In the meantime, the behaviour remains available who cares to 
read the docs and notes.

Just a thought..

Bye
 Shridhar

--
Genderplex, n.: The predicament of a person in a restaurant who is unable to
determine his or her designated restroom (e.g., turtles and tortoises). -- 
Rich Hall, "Sniglets"


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Re: [SQL] [PERFORM] EXTERNAL storage and substring on long strings

2003-08-04 Thread Shridhar Daithankar
On 4 Aug 2003 at 12:14, Scott Cain wrote:
> I forgot about searching--I suspect that application is why I faced
> opposition for shredding in my schema development group.  Maybe I should
> push that off to the file system and use grep (or BLAST).  Otherwise, I
> could write a function that would search the chunks first, then after
> failing to find the substring in those, I could start sewing the chunks
> together to look for the query string.  That could get ugly (and
> slow--but if the user knows that and expects it to be slow, I'm ok with
> that).

I assume your DNA sequence is compacted. Your best bet would be to fetch them 
from database and run blast on them in client memory. No point duplicating 
blast functionality. Last I tried it beat every technique of text searching 
when heuristics are involved.

Bye
 Shridhar

--
There are two types of Linux developers - those who can spell, andthose who 
can't. There is a constant pitched battle between the two.(From one of the post-
1.1.54 kernel update messages posted to c.o.l.a)


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Re: [SQL] [GENERAL] How to view the list of tables?

2005-02-16 Thread Shridhar Daithankar
On Tuesday 15 Feb 2005 3:46 pm, Konstantin Danilov wrote:
> Hello, list!
> I need to view the list of tables in a database. In MySQL I can do it with
> the command "SHOW TABLES". What about PostgreSQL? Can I also see somehow
> the datatypes of tables' fields?

In psql, you can try '\dt' and '\d table name'. Type \? for more commands..

 Shridhar

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