Sql server® 2012 t-sql fundamentals

orderid

productid

PK,FK1

PK

qty

Customers

customerid

PK

companyname

PK

Orders

orderid

orderdate

customerid

FK1

FIGuRE 1-3

  Data model after applying 3NF. 

Informally, 2NF and 3NF are commonly summarized with the sentence, “Every non-key attribute is 

dependent on the key, the whole key, and nothing but the key—so help me Codd.”

There are higher normal forms beyond Codd’s original first three normal forms that involve com-

pound primary keys and temporal databases, but they are outside the scope of this book.

The data Life Cycle

Data is usually perceived as something static that is entered into a database and later queried. But 

in many environments, data is actually more similar to a product in an assembly line, moving from 

one environment to another and undergoing transformations along the way. This section describes 

the different environments in which data can reside and the characteristics of both the data and the 

environment at each stage of the data life cycle. Figure 1-4 illustrates the data life cycle.

OLTP

DW

BISM

DM

DSA

ETL

Integration Services

SQL Server

T-SQL

Analysis Services, PowerPivot

MDX DAX  DMX

FIGuRE 1-4

  The data life cycle. 

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10  

Microsoft SQL Server 2012 T-SQL Fundamentals

Here’s a quick description of what each acronym represents:

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OLTP: online transactional processing

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DSA: data staging area

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DW: data warehouse

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BISM: Business Intelligence Semantic Model

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DM: data mining

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ETL: extract, transform, and load

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MDX: Multidimensional Expressions

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DAX: Data Analysis Expressions

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DMX: Data Mining Extensions