Is it a bad idea to use a single read only Connection?

I am developing a client/server application, where each client request executes in a separate thread. Currently i create a new Connection object for ANY database access. I am wondering if there is any advantage changing this, to use a single Connection object for read only access, but still creating new Connection objects for read/write access.
Does anyone have any opinions on this matter?
I am aware that if i go with this approach, and someone causes a SQL exception on the read only connection that it will be closed. Right now this appears to be the main disadvantage to this approach.

I don't like the single, read-only connection idea.ack
A single connection throughout the execution of the
application has several security disadvantages. It is
also less scalable. I've read other problems
associated with it but I none come to mind at the
moment.What are the security implications that you speak of?
I think for the type of application i am developing,database security is not a concern, as all users are able to access the same tables.
Basically in our application, the security is in the application domain, not the database.

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Currently I am in the process of evaluating different
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queries with huge query criteria and showing the
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