Linq Join Group by 时报Nullable object must have a value. 例如: from s in subject on ch.SubId equals s.SubId join gc in (from aq in question group aq by aq.ChapterId into gaq select new { Id = gaq.Key, Count = gaq.Count(), }) on s.QueId equals gc.Id into…
解决使用DBeaver连接MySQL时报错,其实提示很明显. The server time zone value '�й���ʱ��' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property)to use a more specifc time…
之前在windows上测试是可以正常使用的,但是上传到Linux上后,就报错: Expression # of SELECT list is not in GROUP BY clause and contains nonaggregated column ‘sss.month_id’ which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_…