infoga post i en tabell genom att kopiera en rad i en kolumn från en annan tabell

Du kan inte ha två WHERE-satser i ett uttalande:

insert into RECEIVE(Aname , Permission)
  select Aname , 'select' 
  from SEND
  WHERE Aname = 'GREAME'   <=== WHERE #1
  where not exists         <=== WHERE #2
    (select *  from RECEIVE where aname = 'GREAME' and Permission = 'select')

Du måste ändra den andra delen till ett AND:

insert into RECEIVE(Aname , Permission)
  select Aname , 'select' 
  from SEND
  WHERE Aname = 'GREAME'  
  AND not exists
    (select *  from RECEIVE where aname = 'GREAME' and Permission = 'select')