Solved

interbase and threads

Posted on 2002-06-12
8
147 Views
Last Modified: 2012-05-04
hi

i m doing a two-tire application in delphi 5.0 and interbase 6.0 can any body suggest me how to run interbase querys in thread. If i concurrently run two or more large queries i get the "error cannot read data from connection". I m not just opening the query in the thread but also seeking the last record in order to casch the entire data.

or a better way to casch the larger tables for lookup purposes.

ustad
0
Comment
Question by:ustad
8 Comments
 
LVL 27

Accepted Solution

by:
kretzschmar earned 50 total points
ID: 7074787
>a better way to casch the larger tables for lookup purposes

memory datasets like

rxmemorydataset from the rxlib
(cannot be used as lookupsource, but as cache)

or (just today noticed) the
kbmMemoryTable at http://www.optical.dk/delphi/prod01.htm

both are free and for caching useable

also the tclientdataset may help you,
but for this oraelbis is a better expert than i
(maybe he/she joins into this q)

meikl ;-)
0
 
LVL 7

Assisted Solution

by:Motaz
Motaz earned 50 total points
ID: 7074796
I encounter such problem in lower speed network connection.
Seeking the last record is a very time-consuming operation, try to find alternatives.
You can use Midas Client Data set to cache the table.
Use DataSetProvider, and ClientDataSet.
ClientDataSet is a memory table and can be saved as CDS file or XML file.

Motaz
0
 

Author Comment

by:ustad
ID: 7077898
I would like to use some sort of a component (like client dataset or kbmmemorytable) for casching purpose. but its taking a long time to send this data to these components and threads is causing problems to me. so i would like u experts to suggest a way to achieve this.

0
Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

 
LVL 27

Expert Comment

by:kretzschmar
ID: 7077906
u could use a query like

select * from atable where id = (select max(id) from atable)

if this is not supported by your database then use

select * from atable where id in (select max(id) from atable)

this will return only the last record,
if id is an autoincrment,
if you have an insert-timestmap and not
so an id then use the timestamp instead

you should have an index on the field

meikl ;-)
0
 

Author Comment

by:ustad
ID: 7083274
No i want to casch the entire database which comes to around 100000 records.
0
 
LVL 27

Expert Comment

by:kretzschmar
ID: 7083292
oops,

somewhere i thought that i read something
about a last record

well, every copy/filling needs time

meikl ;-)
0
 
LVL 1

Expert Comment

by:pnh73
ID: 9010661
No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area that this question is:

Split between kretzschmar  and Motaz
Please leave any comments here within the next seven days.
 
PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!
 
Paul (pnh73)
EE Cleanup Volunteer
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

A lot of questions regard threads in Delphi.   One of the more specific questions is how to show progress of the thread.   Updating a progressbar from inside a thread is a mistake. A solution to this would be to send a synchronized message to the…
Creating an auto free TStringList The TStringList is a basic and frequently used object in Delphi. On many occasions, you may want to create a temporary list, process some items in the list and be done with the list. In such cases, you have to…
This video demonstrates how to create an example email signature rule for a department in a company using CodeTwo Exchange Rules. The signature will be inserted beneath users' latest emails in conversations and will be displayed in users' Sent Items…
Need to grow your business through quality cloud solutions? With everything required to build a cloud platform and solution, you may feel like the distance between you and the cloud is quite long. Help is here. Spend some time learning about the Con…

932 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

12 Experts available now in Live!

Get 1:1 Help Now