Help! A cluster method in SQL - 未名空间MITBBS历史存档

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Help! A cluster method in SQL

Help! A cluster method in SQL# Database - 数据库

M*72008-11-26 08:11

1 楼

Hi guys, I have a question of cluster method in SQL.
A table contain 3 columns: rownumber, name, value.
I want to cluster the rows according to their values.
Step 1: First I create another table (tracking table), randomly put some
rows from the data table into this tracking table as the seeds.
Step 2: Then I want to calculate the (ith_value_from_datatable - jth_value_
from_trackingtable)**2, and assign ith row of data table into the jth group
according the the smallest distance calculated above.

n*62008-11-26 08:11

2 楼

My question is:
How many records do you have in the table?
If there are thousands of records, you need thousands of times of computing.
If there are millions of records, ...:( Database performance will be
horrible.
Probably better to process the calculation/clustering outside database.

group
jth

【在 M***7 的大作中提到】

: Hi guys, I have a question of cluster method in SQL.
: A table contain 3 columns: rownumber, name, value.
: I want to cluster the rows according to their values.
: Step 1: First I create another table (tracking table), randomly put some
: rows from the data table into this tracking table as the seeds.
: Step 2: Then I want to calculate the (ith_value_from_datatable - jth_value_
: from_trackingtable)**2, and assign ith row of data table into the jth group
: according the the smallest distance calculated above.