In this 5 minute talk, I try and convince a sceptical audience of PostgreSQL users to work with data models.

1. PG Day, Horwood House, July 9th 2014
(Why you should) Get Modelling!
George McGeachie
Metadata Matters Limited

2. PG Day, Horwood House, July 9th 2014
It’s a lot more than just a Diagram
2
What is a Data Model?

3. PG Day, Horwood House, July 9th 2014 3
Simon and Hannu
say …
Page 59
• Plan a new database
◦ Design structure and estimate size
 A data modelling tool is perfect for that job
• This is an iterative process
◦ Need version control and ability to apply deltas

4. PG Day, Horwood House, July 9th 2014
 Migrate from Oracle to
PostgreSQL
 Reverse-engineer from
database, WSDL, XSDs etc.
 create logical and
conceptual views
 Generate XML Schemas
4
Automate tasks

5. PG Day, Horwood House, July 9th 2014
 Use standard and bespoke
model checks to validate
models
 Enforce naming standards
using a Glossary
 Use your default physical
options
 Create / update your database
 Produce scripts the way you
want them, avoid errors
caused by editing scripts
5
Validate and Generate

6. PG Day, Horwood House, July 9th 2014 6
Model and Generate OLAP
FK_MONTH_RELATIONS_YEAR
FK_BOOK_SAL_RELATIONS_MONTH
FK_BOOK_SAL_RELATIONS_PUBLICAT
Publication
Book Title
Publication Media Type Code
Publication Date
Dollar List Price
ISBN
Page Count
Primary Author Name
Primary Author Pseudonym
Primary Author Royalty Percent
age
CHAR(100)
NUMBER(2)
DATE
NUMBER(5,2)
NUMBER(13)
NUMBER(4)
CHAR(100)
CHAR(100)
NUMBER(2)
<pk>
<pk>
<i>
<i>
not null
not null
null
not null
not null
null
not null
null
null
Book Sales
Year Code
Month Code
Book Title
Publication Media Type Code
Gross Sales Value Amount
NUMBER(2)
NUMBER(2)
CHAR(100)
NUMBER(2)
NUMBER(5,2)
<pk,fk1>
<pk,fk1>
<pk,fk2>
<pk,fk2>
<i1,i2>
<i1,i2>
<i1,i3>
<i1,i3>
not null
not null
not null
not null
not null
Month
Year Code
Month Code
Month Description
CHAR(60)
CHAR(60)
CHAR(256)
<pk,fk>
<pk>
<i1,i2>
<i1>
not null
not null
null
Year
Year Code
Year Description
CHAR(60)
CHAR(256)
<pk> <i> not null
not null
Book Sales - Year_Month
Book Sales - Publication
Measure
Book Sales
Gross Sales Value Amount
Year Code
Month Code
Book Title
Publication Media Type Code
Year_Month
Year Year Code
Year Description
Month Year Code
Month Code
Month Description
<h:1>
<h:2>
<h:3>
Hierarchy_1 <Default> <h>
Publication
Book Title
Publication Media Type Code
Publication Date
Dollar List Price
ISBN
Page Count
Primary Author Name
Primary Author Pseudonym
Primary Author Royalty Percentage
<h:1>
<h:2>
Hierarchy_1 <Default> <h>
Attributes
Hierarchy

7. PG Day, Horwood House, July 9th 2014 7
Simon and Hannu
say …
Page 53
• Understand Database
Dependencies
◦ e.g. Table  View  Procedure

8. PG Day, Horwood House, July 9th 2014
 ETL Jobs
 Forms and Reports
 Applications
 XML Message Schemas
 Regulatory Requirements
 Business Processes
 Use Cases
 JIRA tickets
etc.
8
What about dependencies that
aren’t in your database?
Application
produce
use use
use
use
use
produce
<Undefined>
use
Behind the scenes,
Data objects are being
accessed
Databases are linked to the Physical Data Models that
describe them
Report
Database 1
PostgreSQL
Data Warehouse
Database 2
Teradata
Data Mart
ETL or other Data Movement
Windows Screen
Window form
Web Form
Web form

9. PG Day, Horwood House, July 9th 2014
 Map data movements, generate data
movement scripts, ETL scripts, replication
scripts etc
9
Create Mappings
Marts
ice ss pdm
Post Codes
Lookup
EDW
EDW_PDM
OLTP
PDM
OLTP to EDW EDW to Marts

10. PG Day, Horwood House, July 9th 2014 10
Get Modelling!
Build a database of your database metadata, and join the dots to other stuff
What Tools are there?
The big 3
ERwin, ER/Studio, PowerDesigner
Others
Dezign
Sparx EA
ModelRight
Silverrun
IBM Infosphere Data Architect
Toad Data Modeller
might not all support PG