I need to index on a string field. I'd like the index to index on all items that have a "S" as the leading char but must not include anything that does not have the "S". As in "S12345" would be Ok - "12345" would not be OK. I need to have a index because another program requires that I pass an index to find the right items (I don't have source code for the program).

Anyway I can't figure out how to create this index.

TIA
John