Recursive CTE to build a chain

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-- Recursive CTE to build a chain

declare @T table
(
  name varchar(25),
  value int,
  predecessor varchar(25)
)  

insert into @T
select 'buyingredients', 10, null union all
select 'cook',           12, 'mixingredients' union all
select 'mixingredients',  5, 'buyingredients' union all
select 'eat',             3, 'cook'

;with cte as 
(
  select T.name,
         T.value,
         T.predecessor,
         1 as sortorder
  from @T as T
  where T.predecessor is null
  union all
  select T.name,
         T.value,
         T.predecessor,
         C.sortorder+1 as sortorder
  from @T as T
    inner join cte as C
      on T.predecessor = C.name
)
select C.name,
       C.value,
       C.predecessor
from cte as C
order by C.sortorder

created jun 9 11