AW: AW: Some questions

[Ruslan Zasukhin]

On 4/4/07 4:15 PM, "YSD AG" <support at ysd.ch> wrote:

Hi Fabian, 

> We had finished our new app. using VistaDB. Now if we test the database with
> real world data sets we where astound how fast the speed degrades to nearly
> zero on inserts. Example: adding 70'000 recs with 3 foreign keys went on for
> 10h. 

Well, we have test with 100K inserts into single table with 16 fields of all
types - it takes 3.5 second. Without indexed on table.


> Because there are no self joins supported we had to execute many selects
> in a loop. So if a select takes 10ms and we had 1000 rows as a result of a
> first query we can wait an other 10¹¹ for the final  report. And that are all
> problems on a fast machine holding the db locally with lot of memory and disk
> space left. 

Terrible. 

> Accessing the data in a multiuser environment drops the
> performance by a factor of 8. So a query of, lets say 500 debit out of 15000,
> lasts about 40¹¹ locally and in a multiuser env. it tooks about 5¹.

-----
> Now I had played around with your samples. 100000 inserts with 2 keys in
> 47'' and a select on this database in about 2 msec all on a slow test
> machine - I am impressed.

:-) thank you.

* And this is 100K of SQL inserts, I think. In fact you can speed up this
about 20 (!!!) times if re-write using INSERT with binding.

        INSERT ... VALUES (:1, :2, :3)


* also for BATCH inserts we have ability to DISABLE indexing for a table,
    then ENABLE it back, what will REINDEX fields of table.
    Usually this way in times faster.


P.S. I CC *this part of letter to Valentina list* to keep it in archives of
site. You are one of the first developers who give us info about VistaDB
slowness :-)


-- 
Best regards,

Ruslan Zasukhin
VP Engineering and New Technology
Paradigma Software, Inc

Valentina - Joining Worlds of Information
http://www.paradigmasoft.com

[I feel the need: the need for speed]