Does someone knows what are the circumstances when the sqltext field in this table is empty, or NULL. I am trying to find out what processes are using statistically more time of the server, but looks like there are cases when sqltext for a given process is not filled out, that is remain NULL, or filled out with an empty string. I am sampling this table in every 2 minutes.
I found out that in some cases the client program doing Update Statistics on a collection of tables are responsible for the NULL in sqltext, but it is just the top of an iceberg. The longer running - multiple hours - processes are not leaving any "spur" behind them and I cannot identify with any of the scheduled normal processes, like dbcc based upon its Starttime.
So I need a categorization what kind of processes do not leave any, or just an empty sign in this sqltext field during their run. Even sp_sysmon shows up and sp_dbdump, initiated by Aix scripts.