SELECT student_num,student_name FROM student_score WHERE course_score
2023-07-10 09:02
171
0
0
0
SELECT sno,AVG(score)
FROM student
WHERE score < 60
GROUP BY sno
HAVING COUNT(score)>=2;
2023-07-14 09:07
171
0
0
0
答：该错误主要是由于MySQL的sql_mode配置值设置错误导致的，可以尝试执行以下SQL语句来修复：
SET GLOBAL sql_mode=(SELECT REPLACE(@@sql_mode,STRIC
2023-07-05 09:10
171
0
0
0
一、优化概述二、查询与索引优化分析1性能瓶颈定位Show命令慢查询日志explain分析查询profiling分析查询2索引及查询优化三、配置优化1) max_connections2) back_log3)
2021-12-07 14:36
171
1
1
0
```
SELECT course_id, course_name,
COUNT(CASE WHEN score BETWEEN 100 AND 85 THEN 1 END) AS 100-85,
2023-07-11 10:53
172
0
0
0
SELECT
SUM(CASE WHEN sex=男 THEN 1 ELSE 0 END) AS 男生人数,
SUM(CASE WHEN sex=女 THEN 1 ELSE 0 END) AS 女生人数
F
2023-07-13 09:13
172
0
0
0
1. 查看该数据库实例下所有库大小，得到的结果是以MB为单位mysql>selecttable_schema,sum(data_length)/1024/1024asdata_length,sum(index_len
2021-12-07 14:34
172
0
0
0
SELECT stu_num, stu_name FROM student WHERE stu_num IN (SELECT stu_num FROM student WHERE stu_num != 01 IN
2023-06-20 09:33
173
0
0
0