datalog

[user_1]

Hi All,

I am developing  labview application with access database.

In everyhour there are more than 5000 records and iam plotting graph fetching the records.

Sometimes after fetching the records i have to make updation by changing some fields

of the records and then plot the graph.

For this,what i am doing is first select the records from the database using select query,then update

 records by update table command and again select the records by select quety (so i will get the updated ones)

and then plot the graph.But this is becoming a time consuming process as i have to plot yearly and monthly graphs sometimes.

Can i do the same with a better performance using datalog?

I dont know much about datalog.From where i can get help about datalog?

Thanks......

[mikeporter]

From your description, there are a couple comments I would make:

First, your biggest performance problem is going to be the Access database. I can tell you right now that you are pushing it way beyond what it was every intended to do. You should start looking at alternatives such as Oracle or a good open-source solution like Firebird or MySQL.

Second, given that the data you are working with is apparently some sort of waveform or array data, you should consider storing the data as a BLOB (Binary Large OBject) rather than as individual datapoints. This will significantly improve your performance. To find out more about this, try googling the word "BLOB database" or post follow-up questions here.

One question: is the application that is putting the data into the database originally also written in LabVIEW?

Mike...

PS: One point on terminology. In the LabVIEW environment the word "datalog" refers to something different from what you are discussing. This isn't really a problem except that people who might be able to help might be misled by the subject and not look at your posting.

[user_1]

Thank you so much for your reply sir.

Labview is being used for plotting graph only.

The data from the serial port is coming into the databse in every minute(say) using VB application,i am not much aware

of that as i am involved in labview development..

Apart from migrating into a better database and my previous post, is there a way to achieve the following.

We want to include new feature to the software for that....

What i want is,a way to display the updated database using a datalog.

ie,the datalog should display the database accurately including the last data that is being pushed into the database.

So far i was working entirely with plotting graphs so i dont know anything about datalog when i searched labview help ,

i didnt get much information.Pls can u give me atleat the idea of a what a datalog is and how can i use that for the above purpose.

Thanks once again....

[mikeporter]

Unfortunately, there really isn't a whole lot you can do to improve your performance as long as you are running an Access database - especially with more than one user trying to talk to the database at the same time. This is inherently very very slow and there is nothing you can do about it short of replacing Access with something that is robust enough to handle the job.

Mike...