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mwallman
Creator III
Creator III

Why is using Pick and Match functions combination thought to be faster than nested IF statements?

Hello,

I have heard from some QlikView developers that using the combination of Pick and Match functions is better than using nested IF statements to get the same output.

Can anyone describe why is using Pick and Match functions combination thought to be faster than nested IF statements please? I would like to know the background reasons

1 Solution

Accepted Solutions
8 Replies
evan_kurowski
Specialist
Specialist

Hello Michael,

Without commenting on performance considerations, one reason may be as the number of bucketed logical possibilities grows, from a code comprehension/maintenance perspective, Pick simplifies the syntax compared to the nested IF's.

 

IF(
  IF(
   IF(
    IF(
     IF(
      IF()))))))) //<~ did i miss one, is the paren depth count right?

 


Pick(Value,
1,
2,
3,
4,
)

 

Anonymous
Not applicable

maxgro
MVP
MVP

In script,

I get this result

T << AUTOGENERATE(10000000) 19.995.456 lines fetched

***** if 21/10/2015 19:06:36

T2 << T 19.995.456 lines fetched

21/10/2015 19:06:47

***** pick match  21/10/2015 19:06:47

T1 << T 19.995.456 lines fetched

21/10/2015 19:07:06

with this small test script

T:

Load

Rand() as Rand1,

Ceil(6*Rand()) as Rand2,

IterNo() as TransLineID,

RecNo() as TransID

Autogenerate 10000000

While Rand()<=0.5 or IterNo()=1;

STORE T into T.qvd (qvd);

DROP Table T;

let t=now(); trace ***** if $(t);

T2:

Load

TransLineID,

TransID,

if(Rand2=1, 'a',

if(Rand2=2, 'b',

if(Rand2=3, 'c',

if(Rand2=4, 'd',

if(Rand2=5, 'e',

if(Rand2=6, 'f'

))))))  as Dim2

from T.qvd (qvd);

let t=now(); trace $(t);

DROP Table T2;

let t=now(); trace ***** pick match  $(t);

T1:

Load

TransLineID,

TransID,

Pick(Match(Rand2,1,2,3,4,5,6),'a','b','c','d','e','f') as Dim2

from T.qvd (qvd);

let t=now(); trace $(t);

DROP Table T1;

Anonymous
Not applicable

Hi ,

Can anyone formulate the below with pick and match function .

=if(PG='M'

or PG='P others'

or PG='NE'

or PG='PE'

or PG='HC'

or PG='EC'

or PG='FOOD'

or PG='BIO'

or PG='DIS

or PG='SB'

or PG='Ca'

or PG='PH

or PG='PRO'

or PG='SEYO',dual('Others',26),

if(PG='CP',dual('CPS',12),

if(PG='PC',dual('PCS',10),

if(PG='VC',dual('VCS',11),

if(PG='ALL',null(),PG)))))

evan_kurowski
Specialist
Specialist

I'm sure if you gave this request its own thread, someone would pitch in.

Anonymous
Not applicable

I have assumed the answer already and done it.Thanks for your suggestion future I will follow the same

bramkn
Partner - Specialist
Partner - Specialist

Please delete the last link. It is going to a scam site