Archives of the TeradataForum
Message Posted: Mon, 17 Mar 2008 @ 22:51:49 GMT
<-- Anonymously Posted: Mon, 17 Mar 2008 21:34 -->
I need to create some evenly distributed dummy data tables which will be used to reserve diskspace for capacity on demand. My method for creating these tables was to use a unique primary index populated with integer values in a contiguous number sequence e.g.
CREATE SET TABLE CAPACITY_ON_DEMAND.COD_1 ,NO FALLBACK , NO BEFORE JOURNAL, NO AFTER JOURNAL, CHECKSUM = DEFAULT ( seq_no FLOAT, Col1 CHAR(32000) CHARACTER SET LATIN NOT CASESPECIFIC, Col2 CHAR(32000) CHARACTER SET LATIN NOT CASESPECIFIC) UNIQUE PRIMARY INDEX ( seq_no );
After populating this table with data I ran the following queries which all returned the same value :-
select max(seq_no) from CAPACITY_ON_DEMAND.COD_1 select count(*) from CAPACITY_ON_DEMAND.COD_1 select count(distinct(seq_no )) from CAPACITY_ON_DEMAND.COD_1
However the data in this table has a skew factor of 2. Can anyone tell me why the skew factor is not 0 ? Does anyone have an alternative method which will create a table which has a data skew factor of 0 ?
|Copyright 2016 - All Rights Reserved|
|Last Modified: 27 Dec 2016|