1.group by查询错误

ERROR 1055 (42000): Expression #1 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'qzs.person.id' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

具体参看我的博客文章：MySQL错误1055

不改变环境的条件下，可用

$ select gender from person group by gender;

进行分组查询，但结果只能查询gender这一个字段。