RE: char vs. varchar in a data warehouse

From: Jamadagni, Rajendra <Rajendra.Jamadagni_at_espn.com>
Date: Wed, 05 Jun 2002 10:53:29 -0800
Message-ID: <F001.00475637.20020605105329@fatcity.com>

I am pretty sure I read that oracle puts a character in the field, (it could be on this list or it could be something in oracle 7)

But in a blockdump I just did, for a null row (tow columns both null) there is nothing in the dump, for second row(first col null, second has value) the first column value is shown as '*NULL*' I believe the discussion was something related to how null and empty string is handled. But here again in 816 the empty strings are not shown once again.

Oracle 8161

data_block_dump

---

tsiz: 0x1fb8
hsiz: 0x1a
pbl: 0x095c2c44
bdba: 0x0140337a

flag=-----------
ntab=1
nrow=4
frre=-1
fsbo=0x1a
fseo=0x1fa7
avsp=0x1f7a
tosp=0x1f7a
0xe:pti[0]      nrow=4  offs=0
0x12:pri[0]     offs=0x1fb5
0x14:pri[1]     offs=0x1faf
0x16:pri[2]     offs=0x1faa
0x18:pri[3]     offs=0x1fa7

block_row_dump:
tab 0, row 0, @0x1fb5
tl: 3 fb: --H-FL-- lb: 0x0 cc: 0
tab 0, row 1, @0x1faf
tl: 6 fb: --H-FL-- lb: 0x0 cc: 2
col 0: *NULL*
col 1: [ 1] 41
tab 0, row 2, @0x1faa
tl: 5 fb: --H-FL-- lb: 0x0 cc: 1
col 0: [ 1] 41
tab 0, row 3, @0x1fa7
tl: 3 fb: --H-FL-- lb: 0x1 cc: 0
end_of_block_dump

This proves that I was wrong... but I am pretty sure I remember reading about it ...
Raj

---

Rajendra Jamadagni MIS, ESPN Inc.
Rajendra dot Jamadagni at ESPN dot com
Any opinion expressed here is personal and doesn't reflect that of ESPN Inc.

QOTD: Any clod can have facts, but having an opinion is an art!

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Received on Wed Jun 05 2002 - 13:53:29 CDT