topic Re: Mappinmg Use in QV in QlikView

Mappinmg Use in QV

Sat, 22 Feb 2014 17:13:29 GMT

I am new to Qv,

What is mapping? Why we use mapping? uses

What is apply Map?

Tell me in simple words....

Thanks in Advance..

Venu

Re: Mappinmg Use in QV

sundarakumar — Sat, 22 Feb 2014 17:35:15 GMT

U have prod id and sales in one table

Table1:

prod id sales

1 100

2 200

and u have prod id and prod description in another table

table2:

prod id prod_desc

1 pen

2 paper

now what you do is, u first load the table 2

then while loading table1 u use applymap to map the prod desc from table 2 to table1,

to do this u need a key id field which is going to be prod id in the above example

in script it would be,

table2:

mapping

LOAD prodid,

desc

FROM

(ooxml, embedded labels, table is Sheet1);

table1:

LOAD prodid,

sales,

applymap('table2',prodid)as des

FROM

(ooxml, embedded labels, table is Sheet1);

PFA for more details.

by specifying as mapping while loading the second table u r telling it, that it is loaded only to be mapped by some other table.

so u don't need a drop statement for that(table2)..

moreover if u have more that one desc for the same prod then the first one will be selected the rest is ignored...

hope this helps..

-Sundar

Re: Mappinmg Use in QV

Sat, 22 Feb 2014 17:49:54 GMT

I cant open the QVD file can u help me please

Re: Mappinmg Use in QV

Sat, 22 Feb 2014 18:21:03 GMT

please look This Video it will Clear your Apply map Concept

ApplyMap Function in Qlikview - YouTube

Mapping Load in Qlikview: A Qlikview Tutorial « Learn Qlikview

Apply Map

hope this Helps

Re: Mappinmg Use in QV

sundarakumar — Sat, 22 Feb 2014 18:31:09 GMT

r u using personal edition?

Re: Mappinmg Use in QV

sundarakumar — Sat, 22 Feb 2014 18:35:41 GMT

There is nothing much in the qvw,

create a new qvw, just copy paste the below script in script editor

table2:

mapping

LOAD prodid,

desc

FROM

(ooxml, embedded labels, table is Sheet1);

table1:

LOAD prodid,

sales,

applymap('table2',prodid)as des

FROM

(ooxml, embedded labels, table is Sheet1);

save and execute

and go to table viewer and see how data is loaded into qlikview and compare it with the sources src1 and src2.

Please tell me if u need more clarification...

-Sundar

Re: Mappinmg Use in QV

Sat, 22 Feb 2014 18:37:31 GMT

Hi venu,

i have Example for Apply map

Re: Re: Mappinmg Use in QV

sundarakumar — Sat, 22 Feb 2014 18:49:31 GMT

Pls try now.

-
Sundar

Re: Mappinmg Use in QV

aveeeeeee7en — Sat, 22 Feb 2014 19:04:55 GMT

Hi Venu

Answer 1: The mapping prefix to a Load or Select statement is used for mapping a certain field value or expression to the values in the first column of the mapping table. A mapping table consists of two columns, the fist containing comparison values and the second containing the desired mapping values. Mapping tables will be stored temporarily in the memory and dropped automatically, after script execution.

Answer 2 : The ApplyMap function is used for mapping any field value to a previously loaded mapping table.

This function allows you to lookup a value from a lookup table and fetch the retrieved value into another table.

My experience is when i use Applymap i never face duplicacy of data. It's very useful. It gives Result on the basis of One-to-One Relationship.

Re: Mappinmg Use in QV

maxgro — Sat, 22 Feb 2014 20:02:47 GMT

http://community.qlik.com/blogs/qlikviewdesignblog/2012/09/18/one-favorite-function-applymap

http://www.quickintelligence.co.uk/applymap-is-it-so-wrong/

Re: Mappinmg Use in QV

Sun, 23 Feb 2014 03:23:37 GMT

can u send me please that exmpole...

Re: Mappinmg Use in QV

Sun, 23 Feb 2014 09:39:46 GMT

hi venu

all ready that file i have attached

to my previous comment

you can find that in previous comment

Re: Mappinmg Use in QV

Sun, 23 Feb 2014 14:24:01 GMT

Hi,

Performance wise,if you use apply map .the mapping table will be existed at the time of script execution only and using apply map it avoids duplicates it shows 1 to 1 connection.

but apply map is useful when we want look up to one field in destination table.

Regards

Mahesh