From CTE in SQL to relational algebra

Question

How to pass a CTE in SQL for relational algebra, for example:

with publicacao_cte (nome,nr_publicacoes) 
AS 
( 
select 
candidato.nome, 
Count(1) as nr_publicacoes 
from 
candidato, 
cv, 
ficha_inscricao, 
publicacao_cv 
where 
candidato.bi = ficha_inscricao.bi and 
candidato.bi = cv.bi and 
cv.cod_cv = publicacao_cv.cod_cv 
group by candidato.nome
) 

I’d also like to know how to do the group by and order by in relational algebra.

Answer 1

I found two publications in stackoverflow.com that partially answer the question

https://stackoverflow.com/questions/28665635/algebra-relational-sql-group-by-sort-by-order-by

https://stackoverflow.com/questions/14613953/which-of-the-following-can-you-not-do-in-relational-algebra