CSV Lookup allows a CSV (comma separated values) file to be used as a simple database to help simplify Switch flows. Instead of having to install and configure a database server, design tables, populate with data and write SQL queries, you can simply use a spreadsheet exported to CSV format.
CSV Lookup supports up to 3 "compare" values and up to 4 "lookup" values. Compare values specify which columns in the CSV should be used to locate a matching row. Once a match has been found, CSV Lookup retrieves the values in the "lookup" columns and stores them in the job's private data. These values can be easily retrieved by other elements in your flow using Switch variables.