When interacting with a database, of whatever kind, you will need to establish a connection to the database using the access technology of choice - either Entity Framework, Dapper, or direct ADO (ActiveX Data Objects).

These connections usually have a default timeout, if you don’t specify one.

SQL Server, for example, has a 30-second timeout.

You can, of course, change this when providing a connection string.

I have discussed this extensively in this post - “Dapper Part 8 - Controlling Database Timeouts”

Recently, when reviewing some old code, I came across this line:

SqlMapper.Settings.CommandTimeout = 0

This essentially means that the connection will never time out.

At first glance, this might appear to be a good thing.

It isn’t.

Database connections are expensive, and locking one away will cause problems, as you will eventually run out of connections.

This is especially the case when you create many connections, perhaps in a loop.

When you run out of connections, SQL Server will start to reject any new incoming connections, resulting in angst for users.

Another problem is that on the server side, there may be a bug in your code, perhaps a cursor or some other such construct, that results in an infinite loop.

You will never know about this, as the code will continue to run indefinitely.

TLDR

Do not set database commands to wait infinitely in their connections.

Happy hacking!