I am trying to create partitions on the table which have around 2BIL records and users will always look for the "name", its not possible to create a partition with a list, so we are trying to create a partition-based first letter of the name column. name column has a combination of alpha numeric values.
You can also use MINVALUE and MAXVALUE to mean unbounded at either end of the range.
But is there a particular need that you want to partition this way? It seems like it might be a bit painful to maintain, especially if you're not limiting yourself to ASCII or ANSI characters.
You might want to consider HASH partitioning if you're just looking for a way to keep your tables and indexes to a more manageable size. You've not really mentioned your use case here, so it's hard to give any advice.