Loosing connection to IIS on big queries

[Jim Andersen]

Hi there,

I have a .Net 2.0, vb.net web-app, where the user enters an SQL-string, and
the SQL is sent to an Oracle database.

The result is then shown in a gridview.

But, when the query runs a long time (or returns a large dataset) I loose
connection to the IIS. I get a "server not found or DNS error".

It seems that it happens when data is being sent to the browser. What
happens is, the progressbar on the page slowly fills up, when its almost
filled, the page goes blank (it's being re-freshed with the retrieved data)
and after a while I get the error-message.

I have been using task-manager to check cpu and mem-usage, and can see that
the sql is sent to Oracle, the database works and selects the data, the IIS
works, and then the client/browser works.

If I do (pseudo)
SQLstring="select * from giant_table"
reader=oraclesql.execute SQLstring
me.grid1.datasource=rd

I get the error.

But if I dont bind to a grid but just count the records
SQLstring="select * from giant_table"
reader=oraclesql.execute SQLstring
while reader.read
x=x+1
wend
me.text1.text=x

then it works.

So it seems that the Oracle-end is ok, and that I don't loose the connection
to the database.

What happens, and what can I do?

P.S This is on my local-test IIS "inside" visual studio .net. On the
production server, I use authentication and allow an AD-group access to the
web-app.
When I navigate to the app, I am let in immediately.
When someone who is NOT a member of the AD group navigates to it, the
built-in log-on dialog prompting him for username/password is shown.
When I "loose the connection", it shows the built-in log-on dialog as it
would do if I wasn't a member of the group.

tia
/jim

 

[bruce barker]

most likely the page request is timing out on the server side. the sql
query has a timeout and the page process has a timeout. when the page
times out the connection is closed and the browser report an error.

note: the progress bar is not real in most browsers. the bar will move
even if no data is received.

-- bruce (sqlwork.com)