Difference between left join vs apply map

[#1]

for my knowledge i want to know difference between left join and apply map

i know its good for optimization

but how ??

[himanshi]

Hi,

You don't have to create three mapping tables to get the fields through applymap.You can do it thought one mapping table like the below example.

Map Countries:

Mapping Load 

Country Code,

Country name&'|'&Country Currency as Country data 

Resident Country;

Customers_Tab:

Load *,

Subfield(Applymap('Map Countries',Country Code,null()),'|',1) As Country Name,

Subfield(Applymap('Map Countries',Country Code,null()),'|',2) As Country Currency

Resident Customers;