Applying ‘Lookup’ condition
Example: Apply a lookup on a database reference table or a Value Map based on a source field value and map the result into a target field.
A) Database Reference Table -
Select the target field and then go to Textual Rules and select DB. It will show a function that takes three parameters:
- In the first parameter write the database query and put the Source field that is going to be used for the lookup in the Where clause. Use single quote if the source field is of data type text.
- The second parameter uses the DB Connection Info variable (refer to Help on how to create the DB connection variable).
- The third parameter is either True or False. True means that more than one record is in the result set. False means only one record in the result set. The return response from the query will be mapped to the target field.
B) Value Map -
If the reference data is not in a database but in a CSV file or if you want to create a new reference list within mapping then use the Value Map (VM) Function as shown below. Refer to Mapper Help on how to use Value Map.