Currently I use an Excel lookup to update the metadata in several fields. This works well when the number of records is low. However, when the record count starts increasing it slows right down.
Is there a faster alternative to updating metadata from a separate file than using an excel lookup?
You could try the new Data Repository (available since version 1.5.0). You would have to create a one-time process that imports the contents of your Excel file into the Data Repository. Then, retrieving values from the Repository is done though the same popup menu you use when right-clicking on most fields of most tasks. Options are named Get Repository Value, Get Repository Location, ?just like there already exists Get Metadata Value, or Get Data Location.
Before populating the Data Repository, you would first have to manually create the structure you want to use, using the Data Repository Manager (in the Tools menu). For instance, it could look something like this:
To populate the Data Repository, you could just save the Excel file as a CSV (it if isn’t already), then design a process that reads each value and stores it in a specific Group in the Repository, using the Push to Repository task: