Re: [HACKERS] lztext and parser

From: wieck(at)debis(dot)com (Jan Wieck)
To: zakkr(at)zf(dot)jcu(dot)cz (Karel Zak - Zakkr)
Cc: wieck(at)debis(dot)com, pgsql-hackers(at)postgreSQL(dot)org
Subject: Re: [HACKERS] lztext and parser
Date: 1999-11-25 12:45:50
Message-ID: m11qyHW-0003kGC@orion.SAPserv.Hamburg.dsh.de
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Karel wrote:

> In the lztext_eq(lztext *lz1, lztext *lz2) you use lztext_cmp().
> I'm not sure if it is good, because you must decompress fistly, but
> you don't need information about '<' or '>', you need '=' only. Why
> you not use memcmp() (or other method) for this, and comparate this
> without decompression? Two equal string is equal in a compressed form,
> or not?

For now, yes. But the current lztext implementation is only a
starting poing (still). The final version might have some
runtime customizable parameters for the compression algorithm
(good match size and minimum compression rate). Then, if some
data is stored and the parameters change after, this wouldn't
be true any more.

> All in this letter is comments and suggestions, you can always remove
> this letter to /dev/null :-)

Would never do so. All suggestions are welcome and might
trigger another idea in someone elses head.

Jan

--

#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me. #
#========================================= wieck(at)debis(dot)com (Jan Wieck) #

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