[Solved] MySQL Joining a Table twice

SUM does not take two parameters like you did in sum(fleuge1.Preis,fleuge2.Preis)

sum is an aggregate function , meant to sum all the values on a column, if you want to sum two values from a two distinct sets just do fleuge1.Preis+fleuge2.Preis

if you want to post errors on stack overflow you can just copy them


solved MySQL Joining a Table twice