mysql 8 查詢報錯(sql_mode=only_full_group_by)

Expression #1 of ORDER BY clause is not in GROUP BY clause and contains nonaggregated column 'information_schema.PROFILING.SEQ' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

mysql 5.7之后，查詢如下:
　　select @@sql_mode;
　　如果:ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
默認設置了:
　　sql_mode=only_full_group_by
　　only_full_group_by:使用它就和oracle一樣的group規則，select的列都要在group中，或本身就是聚合列(sum,avg,max,min)才行，只要把它去掉即可。

處理方法：直接在Mysql配置文件中去掉該設置。

sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

常用查詢：

查詢服務器運行狀態
SHOW STATUS LIKE 'Thread%';

查看所有連接的狀態
SHOW FULL PROCESSLIST

查詢服務器的各種設置
SHOW VARIABLES LIKE 'max%';

臨時設置最大連接數(重啟會失效)
SET GLOBAL max_connections = 500