You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'order by pp.orden asc' at line 1
SELECT titulo,descripcion from publicaciones p,publicaciones_publicaciones pp where pp.id_enlace = p.id and p.tipo = 1 and p.activo = 1 and p.id_enlace = order by pp.orden asc
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