Re: Invalidate cache

Roy Hann wrote:

"Cecil Westerhof" <dummy@xxxxxxxx> wrote in message
news:46512088$0$320$e4fe514c@xxxxxxxxxxxxxxxxx
Roy Hann wrote:

"Cecil Westerhof" <dummy@xxxxxxxx> wrote in message
news:465018e1$0$337$e4fe514c@xxxxxxxxxxxxxxxxx

If you have permission to run the accessdb utility, go into the "Users"
submenu, choose your user ID to edit it, and set the "Set trace flags"
switch to "y". Don't forget to save the change. Log back in to pick up
the new privilege.

This works. Thanks.

Good.

But it gives a new question.
I run my queries on a machine that is doing nothing except executing my
queries. Before every query I execute
SET TRACE POINT DM421
But still there is a big difference between the queries. For example when
executing one of the old queries five times it takes: 355,97, 690,16,
379,51, 100,27 and 60,96. When I execute the new version it takes: 2,60,
10,57, 0,99, 0,74, and 1,01 seconds. So it is save to say the new query
is faster, but it is not clear by which factor. In the old query the
difference between the fastest and slowest is 11,3 and in the new query
it is 14,3. Is this normal?

You say you are running the same query repeatedly. Is it exactly the same
query each time, with exactly the same constants in the WHERE clause each
time? I have no explanation for why there would be a difference each
time if it is the same query, except that perhaps the host machine is
*very* busy doing other things as well.

Yes, the script generates a SQL-statement and this is executed repeatadly.
The host machine is only executing VMware. And the virtual machine is only
executing the sql-query.

I'll will make a simpler version of the script and post it here.


There are a couple of presentations on our website that may be of use to
you. Go to www.rationalcommerce.com and click on the Presentations link,
and from there download "Doing More with QEPs than Just Gawping" and "High
Performance Batch Applications".

I'll look.

.

Relevant Pages

  • RE: Dynamically referencing a recordset?
    ... through that recordset to set the query parameters in VBA. ... to be the one who had to modify 1440 queries if there is a change in the ... different table schema, then you need 3, one for each record type. ... This is a database that tracks the production on records in another ...
    (microsoft.public.access.modulesdaovba)
  • Re: Was: what does "serialization" mean?
    ... > the specific queries up front. ... that the NEXT time the query is run the query is fast, ... data base, don't know squat" when in fact the Donald clone doesn't ... >> WHATEVER would probably be a separate query to summarize total sales. ...
    (comp.programming)
  • Re: Official Status of SQLServer 2005 ADP
    ... I have said that the support for SQL passthrough ... queries under MDB was bad and worst than the one offered by ADP while you ... > attempt to "pass through" every Access query against a linked ODBC ...
    (microsoft.public.access.adp.sqlserver)
  • Re: Cluster synchronize
    ... queries per unit time. ... CPU is the ONLY bottleneck. ... increase in query capacity. ... queries that perform sequential I/O or queries performing random I/O. ...
    (microsoft.public.sqlserver.clustering)
  • Re: "Query Too Complex" Errors
    ... few dozens of queries, in the middle of which there's a long chain of ... we've been having a lot of those "Query Too ... some of the complexity in the SQL ... SQL statement you are working on. ...
    (microsoft.public.access.forms)