Blob datatype

[ss7thirty]

What datatype should you use in VB.NET if you are expecting an insanely long string? How many characters does the VB.NET string hold? Is there an equivilent to the Blob datatype? How should you handle insanely large strings in VB.NET?

 

[JohnH]

String is a collection of Chars (16bit) and limited to the Length property which is of Integer type (32bit), this translates to 4GB, but you could run out of memory before that. How to handle such large amounts of data is to split it up and use file storage to hold data that don't need to be in memory.

 

[ss7thirty]

Thank you much for the reply.

So right now I have a Web Service that populates a Data Set based on a few parameters from a database. I use the dataset method getXML() which passes a string back from my Web Servies web method.

This contains 3 fields but a growing ammount of data. File permissions do not let me output the file from the Web Service and I dont want to change anything there.

Which XML object can you pass through web services and which ADO objects should I use in order to do this. Because Data Sets are so slow too.

I need the XML because a VB6 application on a "foreign" PC uses a component that references the above web service and it outputs it to the application path upon loading and then when running uses the "cached" version and works like a charm. But I assume once I have a useless dataset with all that data when I probably should be using some like a data reader or nothing and just get the XML directly somehow. The database is a SQL Server 2000.


Any help is greatly appreciated

 

[JohnH]

Have a read through this web service optimization thread: http://www.vbdotnetforums.com/showthread.php?t=13477
other than that it comes down to the data you need to get, should the returned set be limited perhaps etc.
VB6 is outdated, you should rewrite that application with VB.Net.

 

[ss7thirty]

Once gain thanks for the reply. Unfortunately there are a lot of 3rd party controls that may not work with .NET is what I have been told. I wish I could be using .NET rather than VB6 for this project. Unfortunately, I am told over and over that it will not work. But thanks the link was helpful and I think that with time I will figure out the best way to fix this issue before it becomes one.