Possible depending on your database
Ofc I don't know if this is possible with yours since your not providing version related info.
UDB 0.12.1 (393) for MaNGOS 10545 with SD2 SQL for rev. 1833
Open your database connection with your sql editor (in my case navicat)
Lookup the database
Mangos go to table
command.
in commands lookup name
account set gmlevelgo to the left of that under the field
security and change
4 (owner) to
3(admin)
Restart the server and the command
.account set gmlevel 1/2/3 should work
In case the user is higher of equal of your level you will get error like
You have low security level for this
You cant set your own level out of security reasons.
Though double accounts circumvents this with ease and it shouldn't be hard to remove the failsafe.
But if your wise do not use this on any live server only on a test enviroment.
And if you just copy paste the entire table
command you basicly got al the possible commands in a list.
If you want a ingame listing that would require to edit the core to make a general listing command which is not neccesary imo.
Hope this helps.