Hello,

is it possible to use elevatedb and DBISAM at the same time in one application? The reason is: On the one hand I need Unicode (elevatedb). On the other hand I do not need Unicode, but largefilesupport (DBISAM). I know that Elevatedb also supports largefilesupport, but this is much slower. The table with largefilesupport, the speed is not so important.

Regards
Martin

Martin Pflug

Although I have not done it I am 99% sure there would be no problem at all with this. In Delphi it is very easy to use different data providers at the same time in 1 application, Just include both DBISAM and EDB components (sessions, databases, tables, queries etc.) on the datamodule or in code and link them as usual.

I suppose it would be sensible to have different folder paths for the actual data-files.

Note that if you are using CS / Server connection the two databases connect with different ports by default, so you can easily run both the DBISAM Server and EDB Server at the same time without any changes.

Martin

>is it possible to use elevatedb and DBISAM at the same time in one application? The reason is: On the one hand I need Unicode (elevatedb). On the other hand I do not need Unicode, but largefilesupport (DBISAM). I know that Elevatedb also supports largefilesupport, but this is much slower. The table with largefilesupport, the speed is not so important.

Yes it is possible and there will be no problems. The issues are that your application will be larger, backing up/restoring will be a bit more difficult and if you need to join the two types of table together you'll have to do it in Delphi rather than using SQL.

What is the speed difference and why is it important?

Roy Lambert [Team Elevate]

>What is the speed difference and why is it important?
I have only tested it with dbisam, but i think with elevatedb it would be the same. I used a table with 200 000 random rows and tables with mastersource. With my test-application (Delphi with table in network) i have the result:

without LargeFileSupport:
average 8 ms per row

with LargeFileSupport
average 40 ms per row.

OK, 40 ms isn't slow. But if we made an export ist's a big difference 1 hour - 5 hour.

We have an application with a lot of informations about kitchen appliances. The user can search with FindKey, FindNearest. But sometimes he want to scoll throgh the database. Here we need maximum speed.
In one tablw (with largefielsupport) there are informations like original pictures or pdf in blob fields. Only if the user want to see this informations we have an access to this table.


Thank you for support

Martin

Martin

>We have an application with a lot of informations about kitchen appliances. The user can search with FindKey, FindNearest. But sometimes he want to scoll throgh the database. Here we need maximum speed.
>In one tablw (with largefielsupport) there are informations like original pictures or pdf in blob fields. Only if the user want to see this informations we have an access to this table.

That sounds more like a design problem than a table problem. My guess would be that the speed is caused by linked components rather than the table operations themselves.

Roy Lambert [Team Elevate]

Martin,

<< is it possible to use elevatedb and DBISAM at the same time in one
application? The reason is: On the one hand I need Unicode (elevatedb). On
the other hand I do not need Unicode, but largefilesupport (DBISAM). I know
that Elevatedb also supports largefilesupport, but this is much slower. The
table with largefilesupport, the speed is not so important. >>

That's actually completely backwards - ElevateDB is much, much faster with
large tables (millions of rows) than DBISAM.  There are a lot of
improvements in ElevateDB that were added specifically for performance with
large tables.

My guess is the same as Roy's:  you've got a performance issue at a higher
level than the ElevateDB engine, such as in the TDataSet layer (TEDBTable,
TEDBQuery, data-aware controls).

If you have any other questions, please let me know.

Tim Young
Elevate Software
www.elevatesoft.com

Tim, Roy

I probably expressed myself wrong. I've only tested dbisam. The only thing i do with my testdb ist check and uncheck largefilesupport. If i had a design problem, it would be the same Problem by checked or unchecked largefilesupport. And there was a big performance difference.

<< ElevateDB is much, much faster with large tables (millions of rows) than DBISAM.  

OK, that's nice. I'll try it.

Thank you

Martin