ApplyMap is not the answer here;
Let me explain the utility of applyMap;
Suppose you have table 1 like this:
ID, Country, Sales
1, Tunisia, 500
2, Tunisia, 10000
3, Algeria, 300
and a second table like this:
ID, Name
1, Omar
2, Rayhana
if you do a left join, you'll have
ID, Name, Country, Sales
1, Omar ....
2, Rayhana ....
3 , NULL()....
In this case, we use ApplyMap function to Map the second table to the first one based on the ID and if there is NULL values like in the above example, we can replace It by sthing.
Example of output:
ID, Name, Country, Sales
1, Omar ....
2, Rayhana ....
3 , Missing....
But the syntax is not as you did; please refer to the link Vineth shared with you and here's an example:
table2:
Mapping LOAD
ID,
Name;
from ...;
Table1:
LOAD ID,
Country,
Sales
ApplyMap('table2',ID,'MISSING') as Name;
from ...;
