[MySql] - COUNT + DISTINCT + LEFT JOIN

[cichity74]

Originariamente inviato da Sarachan
Prova così:

SELECT COUNT(*) FROM (SELECT DISTINCT tutorials.id_tutorial FROM tutorials LEFT JOIN tutorial_relation USING(id_tutorial) GROUP BY tutorials.id_tutorial)

Ciao

Messaggio di MySQL: Documentazione
#1248 - Every derived table must have its own alias