data modeling - Snowflake schema dimension -

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this first time i'm working on bi project , pentaho products not yet familiar me, needed know if following models correct , won't face difficulties later when creating hierarchies on bi server !

thank you.

time dimension : enter image description here

complication dimension, every complication can have sub-complications : enter image description here

not idea.

your calendar dimension table should this:

create table calendar (   calendar_id int primary key,   name text not null unique,   date_iso date unique,   year smallint,   quarter smallint,   month smallint,   month_name text   ... );  insert calendar values  (0, 'n/a', null, null, null, null, null), (20130826, 'aug 26, 2013', '2013-08-26', 2013, 3, 8, 'august');

the point of data warehouse ease analysis. making bi analyst 3 joins date not ease analysis.

calendar_id "smart key", i.e. not meaningless surrogate key. calendar table table should use smart key, aids table partitioning date. note nullable fields, allows "n/a" (not available) date. there's no year 0, 0 "n/a" value.

basically, should have 1 level of normalization: fact tables, , dimension tables.


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