Code Example 1:

select o.name, i.name
from sysobjects o, sysindexes i
where o.id = i.id

Code Example 2:

select o.name, i.name
from sysobjects o inner join sysindexes i
on o.id = i.id

Code Example 3:

select o.name, i.name
from sysobjects o, sysindexes i
where o.id = i.id and
indid = 1

Code Example 4:

select o.name, i.name
from sysobjects o inner join sysindexes i on o.id = i.id
where indid = 1

Code Example 5:

update t1
  set t1.col = ............from t1 inner join t2 on t1.col = t2.col

delete t1
  from t1 inner join t2 on t1.col = t2.col