using cursors in c#.net

I'm not really sure I understand exactly but will try to offer some help.

Cursors are slow but is performance an issue?

Are you trying to bind 180000 rows to a datatable? Or are you saying you want to bind one row at a time!?

You could use a stored procedure, select the rows into a temp table with a cursor or for loop etc, then use a data reader to step through each record and add it as a dararow, or you could use an SqlAdapter and bind it to a datatable, but I think that's what you've tried to do and you are running out of memory?

What are you planning to do with this huge datatable?

Use LINQ perhaps?

I have a different twist on this cursor issue.

I have a table with an XML column, some of the XML is really large and there are over 180000 rows of data.  I wrote a small quick and dirty tool to pull this data back and export it as XML for future processing, It all worked in my test ~1000 rows BUT when I bind the datatable to the SQL I run out of memory and it is when the XML row is being run through System.XMl.XmlDocument.

This all makes sense, during the bind operation the datatable creates a row and as part of the row bind for the XML column it rightly creates a XmlDocument object as a column.  It runs out of memory though.
So...  I imidiately thought of a Cursor strategy where by I can bind one row at a time to a System.Data.DataRow and export the row that way.

I do not know how to do that?  Managed C# stored proc??  YUK!!!

Will the data reader idea work, does it actually ONLY bind one row at a time?  I seem to remember that was done programatically andd the default was 25 rows. 

Anyway, let me know what your thoughts are on this.
 

Cursors can cerate performance issues in SQL Server. So dont use it. What is your requirement? You can use Stored procedures to return the data to C# application!!

Thanks -- Vijaya Kadiyala

www.DotNetVJ.Com

but there is no cahnce for u to select data fromdatabase inside while loop.without closing reader..so most of the cases ists apblm.

yo avoid this.

 

use different dataset.and retrivce data to dataset and continue.step

 Hi,

In sql cursor is Forward only Record Set or its equivalent to a table but you are able to navigate only forward.

In dotnet datareader does the same thing.

Thanks,

aru

i think u can do that using sqldatareader.

joust read each row.

for eg:

db is my connection.

db.openconnection();

select is my function for selecting any column f

db.select("select * from table");

 

while( db.reader.Read())

{

do ur calculation ?

}

 

its not..actually cusor do in sql..but one can do it by using this