Hi!
With mappings, you have the option to define the default value when you apply it:
ApplyMap ('MapName', MapField, 'defaultIfNull');
In the default value, you can add another mapping expression. So if you don't have a match in the first map, you can use the second map. Or you could concatenate 2 mapping tables into one.
If you have more complex stuff with a lot of rules, then the best approach woult be to join the main table the other needed tables with the values you want, to a temp table:
TempTable:
Select field1, field2, field3 from yourmaintable.
Left Join
Load field3, field4 resident maptable1; /*These are not qlikview maps, but normal tables that you will delete in the end of the code.*/
Left Join
Load field3, field5 resident maptable2;
Then with a load resident of the temp table, insert your logic to select the
FinalTable:
Load *, if(isnull(Field4), Field5,Field4) as yourfieldName;
Load * resident TempTable;
Drop Fields Field5, Field4 from FinalTable;
Drop tables TempTable, maptable1, maptable2;
Its very important that you use a left Join, in order to mantain the whole data from the temp table.
Hope it helps.
