I've searched the forum for uses of CHECKSUM and havent found a
satisfactory answer.
I need to know when a row changes and I dont care what it was or is, I
just need to know it changed.
Detail:
Hourly I select rows where the record as a create date or change date
of the last 3 days. I am only interested when the address or name
changes, not other columns.
Currently, I might select 30,000 rows that are new or changed, but
turns out that only 100 have address changes and 500 are new. I want
to process the 600, not the 30,000.
My main concern is if some columns change, but the resulting checksum
doesnt. Then I would have missed processing that record.
The column types that I will be tracking are:
"forenames" VARCHAR(50) NULL,
"surname" VARCHAR(51) NULL,
"ADDRESS1" VARCHAR(60) NULL,
"ADDRESS2" VARCHAR(60) NULL,
"ADDRESS4" VARCHAR(50) NULL,
"STATE" VARCHAR(10) NULL,
"ZIP" VARCHAR(20) NULL,
"email" VARCHAR(50) NULL,
"telephone" VARCHAR(10) NULL
(I left off the keys, these are the only fields that I will be using
for the checksum()).
Am I safe? I read about 32 bit CRC and some data changes would go
unnoticed, but not sure if this layout would qualifiy.
TIA
Rob
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