Opening two SQLConnections with the same ConnectionString

Question

I am tracing a bug in a library I did not write myself. When using this library with ASP.NET, I get db connection errors because the SQLConnection seems to get closed when a second Connection is being opened with the same connection string.

Is this documented behaviour? Can opening a new SQLConnection with the same connection string close another SQLConnection object?

From debugging that seems to be the most likely cause for my problems, but I could not find anything on the web to support my theory.

simple way to find this is do a search on the word new and it's probably being created again.. this connection can be a property or static string that's opened and closed by your code.. only create new once.. or add code that will check the Connection.State.. post code where you are creating it.. and the code where it's being closed or the Connection State is closed — MethodMan
– MethodMan, Commented Dec 19, 2011 at 14:56
That should work fine. The issue is more likely to be re-using connections across requests. — SLaks
– SLaks, Commented Dec 19, 2011 at 14:58
@DJ KRAZE: I already found the part where a second connection is being opened with the same connection string. As I wrote, I want to know if its normal that this closes the first connection. — magnattic
– magnattic, Commented Dec 19, 2011 at 14:59
lynn has stated exactly what I was trying to say.. great short and sweet answer @Lynn UPvote definitely.. — MethodMan
– MethodMan, Commented Dec 19, 2011 at 15:01

user596075 · Accepted Answer · 2011-12-19 14:58:32Z

3

No, what will happen is that when you call the SqlConnection.Open() method, even with the same connection string parameters, it will do one of two things: either reuse an unused connection from the pool, or create a new connection. Either way, you will result in non-conflicting SPIDs for SQL Server.

answered Dec 19, 2011 at 14:58

user596075

Sign up to request clarification or add additional context in comments.

Comments

jason · Accepted Answer · 2011-12-19 14:59:53Z

3

Is this documented behaviour?

No.

Can opening a new SQLConnection with the same connection string close another SQLConnection object?

No.

Note that unless you've modified the settings, SQL Server permits 32,767 simultaneous connections. But even then, that would not explain the behavior that you are seeing.

answered Dec 19, 2011 at 14:59

jason

243k35 gold badges436 silver badges532 bronze badges

Comments

Lynn Crumbling · Accepted Answer · 2011-12-19 14:59:21Z

0

In short, opening a new connection with the same connection string will not close your existing connection. However... reusing the already existing object by creating a new reference to a new connection will destroy the connection.

answered Dec 19, 2011 at 14:59

Lynn Crumbling

13.4k8 gold badges61 silver badges98 bronze badges

3 Comments

magnattic Over a year ago

Sorry, I don't understand the last sentence, can you please explain what you mean? How can you reuse an object by creating a new reference to a new object?

Lynn Crumbling Over a year ago

Yes, if I have: SqlConnection conn = new SqlConnection(someconnstring); conn = new SqlConnection(someconnstring); ... then my original connection object will be overwritten with the new one.

jason Over a year ago

@Lynn Crumbling: That is not reusing the existing object. Additionally, that won't necessarily terminate the connection.

Collectives™ on Stack Overflow

Opening two SQLConnections with the same ConnectionString

3 Answers 3

Comments

Comments

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related