The ApplyMap script function is used for mapping any expression to a previously loaded mapping table.
Syntax:
ApplyMap('map_name', expression [ , default_mapping ] )
Arguments:
| Argument | Description |
|---|---|
| map_name | The name of a mapping table that has previously been created through the mapping load or the mapping select statement. Its name must be enclosed by single, straight quotation marks. |
| expression | The expression, the result of which should be mapped. |
| default_mapping |
If stated, this value will be used as a default value if the mapping table does not contain a matching value for expression. If not stated, the value of expression will be returned as is. |
Example:
In this example we load a list of salespersons with a country code representing their country of residence. We use a table mapping a country code to a country to replace the country code with the country name. Only three countries are defined in the mapping table, other country codes are mapped to 'Rest of the world'.
// Load mapping table of country codes:
map1:
mapping LOAD *
Inline [
CCode, Country
Sw, Sweden
Dk, Denmark
No, Norway
] ;
// Load list of salesmen, mapping country code to country
// If the country code is not in the mapping table, put Rest of the world
Salespersons:
LOAD *,
ApplyMap('map1', CCode,'Rest of the world') As Country
Inline [
CCode, Salesperson
Sw, John
Sw, Mary
Sw, Per
Dk, Preben
Dk, Olle
No, Ole
Sf, Risttu] ;
// We don't need the CCode anymore
Drop Field 'CCode';
The resulting table looks like this:
| Salesperson | Country |
|---|---|
| John | Sweden |
| Mary | Sweden |
| Per | Sweden |
| Preben | Denmark |
| Olle | Denmark |
| Ole | Norway |
| Risttu | Rest of the world |