Run time question

[Guest]

1. I have a macro that calls several queries
2. I run the macro against either 13 buildings or a single building
3. Running the macro for 13 building requires 895,000 records to be
processed in the macro
4. Running the macro for a single building takes in the range of 62.000 to
68,000 records
5. The run time for the 13 buildings is 3 hours
6. The run time for a single building is 4 minutes
7. 4 * 13 = 1 hour, not 3 hours
8. Can someone please explain the difference....

thanks

 

[Douglas J Steele]

WIthout knowing what your macro is doing, it's difficult to answer. My guess
is that it has something to do with the indexes on your tables: that what
you're supplying in the WHERE clause of your queries is causing the queries
to run more efficiently.

 

[John Spencer]

What do the queries do? Do they change records? Access may be writing to
the temp file on your hard drive when it has to handle a large number of
records since all the processing may not be able to be handled in RAM.

One solution might be to run the macro thirteen times in sequence.