Long story short: The site got moved to another server. Backed up from old database server (external to the web server) and moved the site to a new server with SQLExpress running locally. Got it up and running seemingly just fine. Until now, several months later, when I add a new FAQ, I got a foreign key constraint error. Problem is, it was on the wrong database. Turns out I did this.

<connectionStrings>
<!-- Connection String for SQL Server 2005 Express -->
  <add name="SiteSqlServer" connectionString="Data Source=.\SQLExpress;Integrated Security=True;User Instance=False;Database=XYZ;" providerName="System.Data.SqlClient" />
<!-- Connection String for SQL Server 2000/2005
  <add name="SiteSqlServer" connectionString="Server=123.456.789.0,1433;Database=ABC;uid=NA;pwd=NA;" providerName="System.Data.SqlClient" />
-->
</connectionStrings>
 

<appSettings>
<!-- Connection String for SQL Server 2005 Express - kept for backwards compatability - legacy modules
  <add key="SiteSqlServer" value="Data Source=.\SQLExpress;Integrated Security=True;User Instance=False;Database=XYZ;" />
-->
<!-- Connection String for SQL Server 2000/2005 - kept for backwards compatability - legacy modules-->
<add key="SiteSqlServer" value="Server=123.456.789.0,1433;Database=ABC;uid=NA;pwd=NA;" providerName="System.Data.SqlClien;" />
 

...

In other words I had the site running partly on one database and partly on the other. What things should I be on the lookout for? Is there a list somewhere of which parts of the system use the which connection?