ERROR 1055 (42000): Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggre
MYSQL执行selectmax(c_id),u_ano,u_bno,c_textfromchatAgroupbyconcat((if(A.u_anoA.u_bno,A.u_bno,A.u_ano,A.u_bno)));遇到的问题:ERROR1055(42000):Expression#1ofSELECTlistisnotinGROUPBYclauseandcontainsnonaggregate