Mapping table essentials
Mapping tables are very useful in QlikView data modeling. Some of the uses of mapping tables include data cleansing, renaming the data source-specific column names with business-friendly names, and providing comments in the script. The following points discuss some of the components and properties of mapping tables:
- Mapping load is used to reduce the number of tables in a data model. Mapping prefix is used to create a mapping table. Mapping tables are used only for field mapping and are automatically dropped after script execution.
- These are usually the look-up tables.
- Mapping tables must have two columns. Even if the table has more columns, you can use only two columns at a time to achieve mapping table functionality. The same table can be used multiple times in case other columns need to be mapped.
- The first column is always a key (ID) column. The second column contains the desired mapping value. The first column field name can differ between the mapping table and...
