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 How to Remember Current ISAM Record for Different Indexes - Q79149
 
 Method 1
 --------
 
 One way to remember the position of the current record according to an
 index is to count the record's relative position (from the beginning or
 end of the table) before changing to another index. This could be
 accomplished by using either MOVEPREVIOUS, with the beginning of the
 table as a reference point, or MOVENEXT, with the end of the table as
 a reference point. However, because this method is sequential, it is
 slow on larger data bases. Listed below is an example, using "One" and
 "Two" as arbitrary index names:
 
 Index1Pos = 0            ' Using index "One".
 WHILE NOT BOF(1)
  MOVEPREVIOUS #1
  Index1Pos = Index1Pos + 1
 WEND
 SETINDEX #1, "Two"
 
 The variable Index1Pos can then be used to find the same record when
 the index is returned to:
 
 SETINDEX #1, "One"
 ' To get to Nth record, MOVENEXT N-1 times:
 FOR i% = 1 to (Index1Pos - 1)
    MOVENEXT #1
 NEXT i%
 
 This will make the original record the current one, thereby achieving
 the desired result. It is important to note that this method will only
 work if no INSERTs, UPDATEs, or DELETEs have been done with the second
 index that would affect the position of any record under the first
 index. Otherwise, the counting method used above may return to a
 different record than expected, because the index may no longer be in
 the original state.
 
 The element Temp.RecordPosition can be used as a marker in correlation
 with the second part of Method 1 (for example, Index1Pos =
 Temp.RecordPosition). Index1Pos can be used to count to the record
 that was current when the index was last used. Also, any time a
 RETRIEVE is done with index "One", the associated record number can be
 displayed (for example, LOCATE 25, 77: PRINT Temp.RecordPosition).
 Note that the RecordPosition field of records would have to be updated
 any time records are INSERTed, UPDATEd or DELETEed, because these
 operations could change the order of the records in the index.