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Index expressions containing the DESCEND() function are supported only when:

•There is no nesting of functions, in other words the DESCEND() function is not nested within other functions.

•You have set SetCollation to #Clipper. Please note that the default collation for VO applications is #Windows !! aaa

•You can even reverse the order of indexes containing DESCEND using the OrderDescend() function/method

 

This is supported:

 

SetCollation(#CLIPPER)

 

INDEX on CUSTOMERID+DESCEND(DTOS(ORDERDATE)) TO Order1

 

INDEX ON AU_LNAME + DESCEND(AU_FNAME) TO AU_NAME

 

INDEX ON DESCEND(CUSTOMERID) + DESCEND(DTOS(ORDERDATE)) TO Orders2

 

INDEX ON DESCEND(CUSTOMERID + DTOS(ORDERDATE)) TO Orders3

 

This is NOT supported:

 

SetCollation(#Windows)                                                 // Wrong Collation !

 

INDEX ON CUSTOMERID+DTOS(DESCEND(ORDERDATE)) TO Order1 // Descend is nested in DTOS()

 

INDEX ON STR(DESCEND(ORDERID),10,0) TO Order2                 // Descend is nested in STR()