The behaviour posted in completly explainable. SQL-Server is working according to the SQL-Standards.

What most people don't know is that SQL "boolean" logic is actually a tripartite logic (a logic with...

Have you checked the SQL-Server ERRORLOG and the eventlog ?

It seems that the SP4-script can not start the SQL server (actually its not getting back the "server started" information from...

This looks like the SP4 SQL script has problems shutting down and restarting your SQL-Server instance. Can you shutdown and restart that service manually ? The restart command is failing...

Technically speaking: SELECT returns all rows where the WHERE condition evaluates to TRUE. A "="comparision with a column containing a NULL is UNDEFINED, so the SELECT never uses that ROW.