Question

I am supposed to get all the rows where an id matches another id…

This is code, I have to link 2 tables…

SELECT *
  FROM acw_papers_web
  WHERE id_paper_web = ( SELECT id_paper_web
                           FROM acw_papers_web_autores
                           WHERE nombre_autor_pw LIKE'%Chicaiza%' )

I get the error: Subquery returns more than 1 row

I noticed why…

But insted of fixing it with a php code (i’m working with that) that gets each id and sends the query for each one of those, I’d like to do it with sql.

Answer 1

You could also use EXISTS() instead of IN(), which might be a little bit faster.

SELECT a.id_paper_web 
  FROM acw_papers_web as a 
  WHERE  
  EXISTS
  (
    SELECT b.id_paper_web 
    FROM acw_papers_web_autores as b
    WHERE b.nombre_autor_pw like '%Chicaiza%' AND b.id_paper_web = a.id_paper_web
  )

DEMO