Qlikview Technical Brief - Conditional Functions

7/24/2019 Qlikview Technical Brief - Conditional Functions

1/15

CONDITIONAL FUNCTIONS

QlikView Technical Brief

April 2014

QlikView 11.2


2/15

Conditional Functions | 2

Contents

INTRODUCTION ................................................................................................................. 3

SET THE SCENE ................................................................................................................ 4FUNCTIONS,FEATURESANDTRICKSUSED .................................................... 4

CLASS() FUNCTION .......................................................................................................... 5

ALT() FUNCTION ................................................................................................................ 8

PICK() FUNCTION ............................................................................................................ 10

IF() FUNCTION ................................................................................................................. 11

MATCH(), MIXMATCH(), WILDMATCH() FUNCTIONS .................................................. 13

SUMMARY ........................................................................................................................ 15

REFERENCES .................................................................................................................. 15


3/15


IntroductionIn this document, the use of the following conditional functions will be

discussed:

Class()

Alt()

Pick()

If()

Match()

Mixmatch()

Wildmatch()

Conditional functions provide a way for us check a condition so that we

can determine what action to perform. All of these functions can be

used in the script as well as in expressions in the user interface (UI).

SUPPORTING MATERIALS QVW.A QVW titled

Conditional Functions.qvw

was created to illustrate how

these conditional functions

can be used.


4/15


Set the Scene

There are times when an expression needs to be evaluated in order to determine the nextcourse of action. QlikView provides a host of functions that return a value based on a condition.

FUNCTIONS, FEATURES AND TRICKS USED

The following string functions will be defined in this document:

Class()

Alt()

Pick()

If()

Match() Mixmatch()

Wildmatch()


5/15


Class() Function

The Class() function is defined in QlikView Help this way:

class(expression, interval [ , label [ , offset ]])

Creates a classification of expressions. The bin width is determined by the

number set as interval. The result is shown as a


6/15


Using the offset parameter changes the starting point from 0 to the parameter. In the examplebelow the offset was set to 3.

Class([Number Of Days Late],30,'days',3) as[Days Late]

Using class allows you to create a chart like the one below that shows the number of late orders

based on various buckets.


7/15



8/15


Alt() Function

The Alt() function is defined in QlikView Help this way:

alt(case1[ , case2 , case3 , ...] , else)

The alt function returns the first of the parameters that has a valid numberrepresentation. If no such match is found, the last parameter will be returned. Anynumber of parameters can be used.

The Alt() function can be used in the script or in an UI expression and will return the first valid

number representation (including dates). If no match is found then the last parameter will be

returned. An example of how this function can be used is to check the format of a date field.

Assume there is a date field that has dates in various formats. The Alt() function can be used to

check these formats and to indicate which dates do not match a format listed. In the example

below only dates with the format M/D/YYYY or DD/MM/YYYY is ok otherwise Invalid Date

should be displayed.

ValidatedDates:

LOAD

TempDate,

Alt(Date#(TempDate, 'M/D/YYYY'), Date#(TempDate, 'DD/MM/YYYY'),

Date#(TempDate, 'DD/MM/YYYY'), Date#(TempDate, 'YYYY-MM-DD'), Date#(TempDate,'DD.MM.YYYY'), 'Invalid Date') asValidatedDate

INLINE[

TempDate

1/1/2014

1/6/2014

01/08/2014

25/01/14

25/1/2014

40729

30.02.2014

16.08.2014

31/12/2013

20/05/2014

2014-02-272013-11-20

];

In the script above there is a Dates table with dates in various formats. In the ValidatedDates

table, the Alt() function is used to check the dates. If the format matches one of the parameters

then it is returned. If the format of the date does not match any of the parameters, then Invalid

Date is returned. Many parameters can be used in the Alt() function if necessary. The order of

the parameters indicates the priority order so that can be used to determine how the dates


9/15


should be interpreted. For example, should 7/4/2014 be interpreted as 4thof July in the US or 7

th

of April in the UK.

The result of the script can be seen in the table below. The TempDate is the original date and

the ValidatedDate is the value returned by the Alt() function.

Notice that 40729 did not match the format thus Invalid Date was returned.

The Alt() function can also be used to display a value other than null when an expression results

in null. For example, assume you have an expression that multiplies two values and one of the

values is null, the Alt() function can be used to display 0 (or something else) instead of null like

this: Alt(A*B, 0).


10/15


Pick() Function

The Pick() function is defined in QlikView Help this way:

pick(n, expr1[ , expr2,...exprN])

Returns the n:th expression in the list. n is an integer between 1 and N.

The Pick() function will return the expression/value corresponding to the expression that

matches the first parameter. For example, Pick(2, A, B, C) will return B because B is the

second expression and Pick(Number, Sum(1+1), Sum(2+2), Sum(3+3), Sum(4+4), Sum(5+5))

will return 6 if Number = 3.

This function is excellent when you want to generate a random field value, e.g.

Pick(Ceil(3*Rand()),'A','B','C') asRandomDim

This random field was added to the Salesrep table and randomly stored A, B or C in the

RandomDim field. Pick() can be used in both the script and in an UI expression.


11/15


If() Function

The If statement is defined in QlikView Help this way:

if(condition , then , else)

The three parameters condition, then and else are all expressions. The first one,condition, is interpreted logically. The two other ones, then and else, can be ofany type. They should preferably be of the same type. If condition is true, thefunction returns the value of the expression then. If condition is false, the functionreturns the value of the expression else.

An If() statement can be used in the script or in an UI expression. The first parameter checks a

condition and returns the then parameter if it is true or the else parameter if the condition isfalse. There are many reasons to use an if statement. In a script, the if statement can be used

to create a flag as seen in the script below.

SalesDetails:

LOAD

[Address Number],

BudKey,

AggKey,

DateKey,

[Order Number],

[Item-Branch Key],

[Sales Rep],

[Item Class],CustKey,

[Line Desc 1],

[Invoice Number],

[Sales Quantity],

[Actual Delivery Date],

[Last Status],

[Number Of Days Late],

Class([Number Of Days Late],30) as[Days Late],

if([Number Of Days Late]>=30,1,0) as[30 or More Days Late],

[Order Status],

[Line Number],

[Item Number],

[Line Type],

[List Price],

[Sales Cost Amount],[Order Margin],

[Open Order Cost Amount],

[Discount Amount],

[Invoice Date],

[Unit Price],

[Promised Delivery Date],

[Open Order Amount],

[Sales Amount],

[BackOrder Amount],

[Sales Price]

FROM$(vPath)SalesDetails.qvd (qvd);


12/15


In this script a flag ([30 or More Days Late]) is created to indicate if an order is 30 or more days

late. If it is 30 or more dates late, then the flag is set to 1 (true) otherwise it is set to 0 (false).

This flag can then be used in the UI as a list box or in a set analysis expression.


13/15


Match(), Mixmatch(), Wildmatch() Functions

The Match(), Mixmatch() and Wildmatch() functions are similar in that they perform acomparison between the first parameter and the expression parameters.

The Match() function is defined in QlikView Help this way:

match(str, expr1 [ , expr2,...exprN ] )

The match function performs a case sensitive comparison.

The Match() function does a case sensitive comparison between the first parameter and the

expressions. It can be used in the script or in a UI expression. In the expression Match(X, Jan,

Feb, Mar, Apr), 1 is returned if X=Jan, 2 if X=Feb and so on. If X=Dec, then 0 is returned.

The Matchmix() function is defined in QlikView Help this way:

mixmatch( str, expr1 [ , expr2,...exprN ] )

The mixmatch function performs a case insensitive comparison.

The Mixmatch() function does a case insensitive comparison between the first parameter and

the expressions. It can also be used in the script or in a UI expression. In the expression

Mixmatch(X, Jan, Feb, Mar, Apr), 1 is returned if X=Jan, 2 if X=feb and so on. If X=Dec,

then 0 is returned. With Mixmatch() the case does not matter.


14/15


The Wildmatch() function is defined in QlikView Help this way:

wildmatch( str, expr1 [ , expr2,...exprN ])

The wildmatch function performs a case insensitive comparison and permits theuse of wildcard characters ( * and ?) in the comparison strings.

The Wildmatch() function does a case insensitive comparison between the first parameter and

the expressions and wildcard characters can be used. It can be used in the script or in an UI

expression. In the expression Wildmatch(X, Ja*, F?b, mar, Apr), 1 is returned if X=jan, 2 if

X=Feb, 3 is returned if X=Mar and so on. If X=Dec, then 0 is returned.


15/15


Summary

In this technical brief we looked at 7 conditional functions: Class(), Alt(), Pick(), If(), Match(),Mixmatch() and Wildmatch() that can be used in expressions and the script to do a comparison

or check a condition before deciding the next course of action.

References

Below are supporting materials that may be helpful:

QVW Conditonal Functions.qvw - example expressions and scripts of all conditional functions

discussed in this document.

www.qlikviiew.com

2012 QlikTech International AB. All rights reserved. QlikTech, QlikView, Qlik, Q, Simplifying Analysis for Everyone, Power of Simplicity, New Rules, The Uncontrollable Smile and other QlikTechproducts and services as well as their respective logos are trademarks or registered trademarks of QlikTech International AB. All other company names, products and services used herein aretrademarks or registered trademarks of their respective owners. The information published herein is subject to change without notice. This publication is for informational purposes only, withoutrepresentation or warranty of any kind, and QlikTech shall not be liable f or errors or omissions with r espect to this publication. The only warranties for QlikTech products and services are those thatare set forth i n the express warranty statements accompanying such products and services, if any. Nothing herein should be construed as constituting any additional warranty.

Documents

Qlikview Technical Brief - Conditional Functions