LA ACCIÓN CONTRARIA AL DEBER OBJETIVO DE CUIDADO

There are many different ways to define type of data. One way is to define type as data type. In this manner, the Satellites can be divided into different pieces based on their data types. History has shown that the benefits of this approach are as follows:

• Create a fixed width row for bits, integers, dates/times (all non-varchar components)

• Create variable width rows for all varchar / char attributes

• Create variable length BLOB / CLOB / LOB objects

• Dramatically increase compression rates for data sets

• Decrease overall storage needs (by reducing the potential for chained rows)

• Easier management and maintenance

• No “guess work” involved in defining new Satellites

• Easier indexing strategies

• Easier partitioning strategies

• Easier Query Parallelism

• End Result? Increased performance

Of course we can’t ignore the nature of the query set. When classifying attributes into different Satellites by data type, it is important to remember the queries that will be grabbing the data sets – and put it in context with the platform that the queries are running on. For instance, if the platform is Teradata, or IBM DB2 UDB EEE / MPP then the queries and parallelism will work quite well. Or if the platform is SQLServer 2008 R2/MPP, or Oracle SMP Big Iron with Partitioning and Parallel query, then the queries will work quite well.

If the platform is a DB2 based AS/400 – then normalizing the Satellite goes against the

performance principles of the HFS (hierarchical file system). Also, if the hardware is under-powered, under-sized, or the database hasn’t been tuned appropriately then the queries might not run so well.

Supe

er Charge Yo

an Linstedt 2 hermore – th nged). The ri physically loo ered in the Da

-site at: http:

he interest of ws a split of S

is known as es into differ abases follow gle column in of the benef ming conventi meric, either d

ntimeters) or mns – both s

our Data Ware

2010-2011, a he database

ise of NOSQL ok at partition ata Vault Imp ://danLinsted f discussion,

SAT_PROD fr

Figu vertical part ent groups ti w for perform to its own ta fits of this tec

ons. For inst decimal or flo in (inches).

should be sto

ehouse

all rights rese industry is ch L (like HADOO ning data sets plementation

dt.com and for the p rom Figure

6-re 6-3: Satel titioning. Tha ed together ance, but the able structure chnique is it

tance: I woul oat – unless

purposes of d -2 (above) int

lites Split by t is: the act o by the same ey take it to t e.

begins to sho d argue that of course the ase, the size umeric Satel

d by the time s, and column l beyond the the one-on-o

demonstratio to multiple S

Type Of Data of splitting co key. This is the extreme b

ow potential size nvarcha e size include and size me llite.

P

http:/

this is publis nar database scope of this one on-line co

on, the Figure Satellites.

a Option 1 olumns up (o

a concept th by splitting (n

mismatches ar(5) might b es a measure easurement s

Page 117 of 1

//LearnData shed, will hav es will change s book, and w oaching secti

e below (Figu

or normalizing hat the colum normalizing)

s for data typ be better off a

ement like cm should be se

152

Upo

n further insp sibly as part o manage its m

umerous as t your data by uping suits yo Splitting Sat e of change is ny different w

s each eleme of change of of change fo nging data ca ormalized in

ough compre piles up over s in. The imp er temp area dware level).

pection: Days of the date d metadata on the stars in t y type; spend our needs be

ellites by Rate s a similar to ways. Howeve

ent or group f cell phone n or that perso auses data s to a single S

Figu ession in the r time. All th pact can be s as (needed fo

sToManufact ata types Sa tology. Onto the sky. In ot

numbers for ns’ address.

pace explosi Satellite, and

ure 6-4: Sate database off is “extra data seen in longe or queries), a

ture could be atellite. It all ological defin ther words – in the design

or classificatio rticular case change in re an individua Lumping all on. Figure 6 changes at d

llite Data Rat fers a little b a” is recordin er loading tim nd slower qu

e seen as a n depends on itions/classif

there are m n phase whic

on of data. R

te of Change it of relief fro ng little to no mes, longer b

ueries overall

numeric (as it how the bus fications for f

illions of com h manner of

Rate of chang e of change o each other.

ponentially hi changing da example of d es.

e Example om the repeti

changes to t backup times

l (more I/O g

t is now), or q iness desires fields in the t mbinations (w classificatio

ge can be de refers to: how In other wo gher/faster t ta with other data that is

escribed in w fast

Supe

er Charge Yo

an Linstedt 2 he above exa er day, but th ew row in this exes for the fi ng for which i ans that if you

quickly. design of the nge, this allow

gure 6-5, we ellite (becaus e efficient an the row-size

our Data Ware

2010-2011, a mple, the ce e name and s instance ca ields also exp index is the b u index the N

you think it lo ng this for ye

g over 10x th his table with nd addresses

e number cha h or row size

is much sma

ehouse

all rights rese ll phone cha address may

n be painful.

plode. What best to use fo Name or the A

ooks OK now ars with a typ he amount of h 100 million (assuming e anges. The p

of the table.

of attempts can be mitig to settle in to

Figure 6-5: S sk space com

s were show The contact aller, the inde

erved nges every d y change onc . Not only do

’s worse, is t or SQL) is dra Address colu

, or you don’

pe 2 dimensi f data that yo rows in it, w ach changed performance

at database gated very eas

o predictable

atellite Split mpression im n). As it turn phone Satel ex coverage is

ay. The Pho ce a year or le oes the data s he coverage amatically red

mns, their se

t see the har on), then jus ou currently h when in reality about 15 tim is dreadful to

optimization sily by splittin e patterns of

by Rate Of C mediately ta ns out, storing

lite still has a s better, and

P

http:/

ne number m ess. The rigo set in the tab (that’s the in duced by dup electivity will

rm in this (be st try to imag have. In othe

y you only ha mes total), an o think about

n, all because ng the Satell repetition.

Change ke place in th g the informa all the chang d the perform

Page 119 of 1

//LearnData may change e

or required fo ble explode, t nternal datab plicate data;

become very

ecause you’ve gine this

er words, ave 6.6 millio nd 100 million t because of

e of a poor ch ite up by rate

he contact n ation once is ges and all th mance is faste

152

aVault.com every or loading

the he history,

er.

In document DERECHO PENAL I, PRIMER PARCIAL (página 99-104)