Syntax

SYNCKEY({old-field-name|oldfile-position,length}[,newfile-position]

[,NOKEY|,ASCENDING|,DESCENDING][,NOPRINT|PRINT])

SYNCKEY(old-field-name,length{,new-field-name|,newfile-position}[,NOKEY|,ASCENDING|,DESCENDING][,NOPRINT|PRINT])