Function used in the creation and searching of descending order tag indexes
The DBXDESCEND() function is used in the creation and searching of descending order tag indexes. It can be used on CHARACTER, NUMERIC, LOGICAL and DATE fields. For character fields, the function operates by subtracting the ASCII code for each character from 255. For numeric fields, the sign is reversed. Logical Falses become .T. (true) and logical Trues become .F. (false). The DBXDESCEND() function can be used to search in DATE indexes created with the DESCENDING keyword, but use outside the context of an index search will result in an Invalid date being returned.
For index tags created using the DESCENDING keyword, the DBXDESCEND() function must be used in SEEK index searches.
index on name tag descendname descending seek dbxdescend("Smith")