专栏首页Java帮帮-微信公众号-技术文章全总结【数据库】MySQL经典面试题(练习)

【数据库】MySQL经典面试题(练习)

【数据库】MySQL经典面试题(练习)

一、删除除了学号字段以外,其它字段都相同的冗余记录,只保留一条!(也就是要删除凤姐和田七中一条重复数据只留一条)

要求结果数据:

原始数据:

CREATE TABLE tbl_students (

id number(32) NOT NULL,

name varchar(10) DEFAULT NULL,

sax varchar(10) DEFAULT NULL,

age number(6) DEFAULT NULL,

PRIMARY KEY (id)

)

insert into tbl_students (id, name, sax, age) values('2','李四','男','21');

insert into tbl_students (id, name, sax, age) values('3','张三','女','17');

insert into tbl_students (id, name, sax, age) values('4','李四','男','12');

insert into tbl_students (id, name, sax, age) values('6','凤姐','女','20');

insert into tbl_students (id, name, sax, age) values('5','凤姐','女','20');

insert into tbl_students (id, name, sax, age) values('7','田七','男','18');

insert into tbl_students (id, name, sax, age) values('1','田七','男','18');

insert into tbl_students (id, name, sax, age) values('8','张三','男','17');

答案:

mySql

DELETE FROM student WHERE sid NOT IN (SELECT sid FROM ((SELECT MIN(sid) sid FROM student GROUP BY sName,sSex ))t)

oracle:

DELETE FROM student WHERE sid NOT IN(SELECT MIN(sid) sid FROM student GROUP BY sName,sSex )

二、查询各科成绩都及格的学员

(要求查询出参加考试的各科成绩都高于60分,不管参加了多少科考试)

要求结果:

表:

CREATE TABLE tbl_score (

id NUMBER(10) NOT NULL,

username varchar(20) DEFAULT NULL,

course varchar(20) DEFAULT NULL,

score NUMBER(10) DEFAULT NULL,

PRIMARY KEY (id)

)

数据:

insert into tbl_score (id, username, course, score) values('1','张三','语文','50');

insert into tbl_score (id, username, course, score) values('2','张三','数学','80');

insert into tbl_score (id, username, course, score) values('3','张三','英语','90');

insert into tbl_score (id, username, course, score) values('4','李四','语文','70');

insert into tbl_score (id, username, course, score) values('5','李四','数学','80');

insert into tbl_score (id, username, course, score) values('6','李四','英语','80');

insert into tbl_score (id, username, course, score) values('7','王五','语文','50');

insert into tbl_score (id, username, course, score) values('8','王五','英语','70');

insert into tbl_score (id, username, course, score) values('9','赵六','数学','90');

答案:

select username,scor from tbl where id not in (select id from tbl where score < 60)

MySQL题型练习

表(MYSQL)

Student(sid,Sname,Sage,Ssex) 学生表

CREATE TABLE student (

sid varchar(10) NOT NULL,

sName varchar(20) DEFAULT NULL,

sAge datetime DEFAULT '1980-10-12 23:12:36',

sSex varchar(10) DEFAULT NULL,

PRIMARY KEY (sid)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Course(cid,Cname,tid) 课程表

CREATE TABLE course (

cid varchar(10) NOT NULL,

cName varchar(10) DEFAULT NULL,

tid int(20) DEFAULT NULL,

PRIMARY KEY (cid)

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

SC(sid,cid,score) 成绩表

CREATE TABLE sc (

sid varchar(10) DEFAULT NULL,

cid varchar(10) DEFAULT NULL,

score int(10) DEFAULT NULL

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

Teacher(tid,Tname) 教师表 CREATE TABLE taacher (

tid int(10) DEFAULT NULL,

tName varchar(10) DEFAULT NULL

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

数据:(MySQL)

insert into taacher(tid,tName) values (1,'李老师'),(2,'何以琛'),(3,'叶平');

insert into student(sid,sName,sAge,sSex) values ('1001','张三丰','1980-10-12 23:12:36','男'),('1002','张无极','1995-10-12 23:12:36','男'),('1003','李奎','1992-10-12 23:12:36','女'),('1004','李元宝','1980-10-12 23:12:36','女'),('1005','李世明','1981-10-12 23:12:36','男'),('1006','赵六','1986-10-12 23:12:36','男'),('1007','田七','1981-10-12 23:12:36','女');

insert into sc(sid,cid,score) values ('1','001',80),('1','002',60),('1','003',75),('2','001',85),('2','002',70),('3','004',100),('3','001',90),('3','002',55),('4','002',65),('4','003',60);

insert into course(cid,cName,tid) values ('001','企业管理',3),('002','马克思',3),('003','UML',2),('004','数据库',1),('005','英语',1);

(扩展Oracle)

ORACLE(表+数据)

CREATE TABLE student (

sid varchar2(10) NOT NULL,

sName varchar2(20) DEFAULT NULL,

sAge date ,

sSex varchar2(10) DEFAULT NULL,

PRIMARY KEY (sid)

)

CREATE TABLE course (

cid varchar2(10) NOT NULL,

cName varchar2(10) DEFAULT NULL,

tid number(20) DEFAULT NULL,

PRIMARY KEY (cid)

)

CREATE TABLE sc (

sid varchar2(10) DEFAULT NULL,

cid varchar2(10) DEFAULT NULL,

score number(10) DEFAULT NULL

)

CREATE TABLE teacher (

tid number(10) DEFAULT NULL,

tName varchar2(10) DEFAULT NULL

)

insert into course(cid,cName,tid) values ('001','企业管理',3);

insert into course(cid,cName,tid) values ('002','马克思',3);

insert into course(cid,cName,tid) values ('004','数据库',1);

insert into course(cid,cName,tid) values ('005','英语',1);

insert into sc(sid,cid,score) values ('1001','001',80);

insert into sc(sid,cid,score) values ('1001','002',60);

insert into sc(sid,cid,score) values ('1001','003',70);

insert into sc(sid,cid,score) values ('1002','001',85);

insert into sc(sid,cid,score) values ('1002','002',70);

insert into sc(sid,cid,score) values ('1003','004',90);

insert into sc(sid,cid,score) values ('1003','001',90);

insert into sc(sid,cid,score) values ('1003','002',99);

insert into sc(sid,cid,score) values ('1004','002',65);

insert into sc(sid,cid,score) values ('1004','003',50);

insert into sc(sid,cid,score) values ('1005','005',80);

insert into sc(sid,cid,score) values ('1005','004',70);

insert into sc(sid,cid,score) values ('1003','003',10);

insert into sc(sid,cid,score) values ('1003','005',10);

insert into student(sid,sName,sAge,sSex) values ('1001','张三丰',to_date('1980-10-12 23:12:36','YYYY-MM-DD HH24:MI:SS'),'男');

insert into student(sid,sName,sAge,sSex) values ('1002','张无极',to_date('1995-10-12 23:12:36','YYYY-MM-DD HH24:MI:SS'),'男');

insert into student(sid,sName,sAge,sSex) values ('1003','李奎',to_date('1992-10-12 23:12:36','YYYY-MM-DD HH24:MI:SS'),'女');

insert into student(sid,sName,sAge,sSex) values ('1004','李元宝',to_date('1980-10-12 23:12:36','YYYY-MM-DD HH24:MI:SS'),'女');

insert into student(sid,sName,sAge,sSex) values ('1005','李世明',to_date('1981-10-12 23:12:36','YYYY-MM-DD HH24:MI:SS'),'男');

insert into student(sid,sName,sAge,sSex) values ('1006','赵六',to_date('1986-10-12 23:12:36','YYYY-MM-DD HH24:MI:SS'),'男');

insert into student(sid,sName,sAge,sSex) values ('1007','田七',to_date('1981-10-12 23:12:36','YYYY-MM-DD HH24:MI:SS'),'女');

insert into teacher(tid,tName) values (1,'李老师');

insert into teacher(tid,tName) values (2,'何以琛');

insert into teacher(tid,tName) values (3,'叶平');

SQL问题:

1.查询“001”课程比“002”课程成绩高的所有学生的学号; select a.sid from (select sid,score from SC where cid='001') a,(select sid,score from SC where cid='002') b where a.score>b.score and a.sid=b.sid;

2、查询平均成绩大于60分的同学的学号和平均成绩; select sid,avg(score) from sc group by sid having avg(score) >60;

3、查询所有同学的学号、姓名、选课数、总成绩; select Student.sid,Student.Sname,count(SC.cid),sum(score) from Student left Outer join SC on Student.sid=SC.sid group by Student.sid,Sname

4、查询姓“李”的老师的个数; select count(distinct(Tname)) from Teacher where Tname like '李%';

5、查询没学过“叶平”老师课的同学的学号、姓名; select Student.sid,Student.Sname from Student where sid not in (select distinct( SC.sid) from SC,Course,Teacher where SC.cid=Course.cid and Teacher.tid=Course.tid and Teacher.Tname='叶平');

6、查询学过“001”并且也学过编号“002”课程的同学的学号、姓名; A:select Student.sid,Student.Sname from Student,SC where Student.sid=SC.sid and SC.cid='001'and exists( Select * from SC as SC_2 where SC_2.sid=SC.sid and SC_2.cid='002');

B:SELECT s.sid,s.sName

FROM student s, (SELECT sid,COUNT(cid) FROM sc WHERE cid IN ('001','002') GROUP BY sid HAVING COUNT(cid)>=2) t WHERE s.sid = t.sid

7、查询学过“叶平”老师所教的所有课的同学的学号、姓名; select sid,Sname from Student where sid in (select sid from SC ,Course ,Teacher where SC.cid=Course.cid and Teacher.tid=Course.tid and Teacher.Tname='叶平' group by sid having count(SC.cid)=(select count(cid) from Course,Teacher where Teacher.tid=Course.tid and Tname='叶平'));

8、查询课程编号“002”的成绩比课程编号“001”课程低的所有同学的学号、姓名; 1>Select sid,Sname from (select Student.sid,Student.Sname,score ,(select score from SC SC_2 where SC_2.sid=Student.sid and SC_2.cid='002') score2 from Student,SC where Student.sid=SC.sid and cid='001') S_2 where score2 <score;

2>SELECT s.sid,s.sName FROM student s,

(SELECT sid,score FROM sc WHERE cid = '001') sc_1,

(SELECT sid,score FROM sc WHERE cid = '002') sc_2

WHERE sc_1.sid = sc_2.sid AND s.sid = sc_2.sid AND sc_2.score < sc_1.score

9、查询所有课程成绩小于60分的同学的学号、姓名; select sid,Sname from Student where sid not in (select Student.sid from Student,SC where S.sid=SC.sid and score>60);

10、查询没有学全所有课的同学的学号、姓名; 1>select Student.sid,Student.Sname

from Student,SC where Student.sid=SC.sid group by Student.sid,Student.Sname having count(cid) <(select count(cid) from Course);

2>SELECT s.sid,s.sname FROM student s,

(SELECT sid,COUNT(cid) FROM sc GROUP BY sid HAVING COUNT(cid) < (SELECT COUNT(cid) FROM course) )t

WHERE s.sid = t.sid

11、查询至少有一门课与学号为“1001”的同学所学相同的同学的学号和姓名; select sid,Sname from Student,SC where Student.sid=SC.sid and cid in (select cid from SC where sid='1001');

13、把“SC”表中“叶平”老师教的课的成绩都更改为此课程的平均成绩; UPDATE sc,(SELECT c.cid,AVG(score) avgs FROM sc,course c,teacher t WHERE sc.cid = c.cid AND

c.tid = t.tid AND t.tName = '叶平' GROUP BY c.cid)sc_2 SET sc.score = sc_2.avgs WHERE sc.cid = sc_2.cid

14、查询和“1002”号的同学学习的课程完全相同的其他同学学号和姓名; select sid from SC where cid in (select cid from SC where sid='1002') group by sid having count(*)=(select count(*) from SC where sid='1002');

15、删除学习“叶平”老师课的SC表记录; DELETE FROM sc WHERE sc.cid IN (SELECT sc.cid FROM course c ,teacher t WHERE sc.cid = c.cid AND c.tid = t.tid AND t.tName = '叶平')

17、按平均成绩从高到低显示所有学生的“数据库”、“企业管理”、“英语”三门的课程成绩,按如下形式显示: 学生ID,,数据库,企业管理,英语,有效课程数,有效平均分 SELECT sid as 学生ID ,(SELECT score FROM SC WHERE SC.sid=t.sid AND cid='004') AS 数据库 ,(SELECT score FROM SC WHERE SC.sid=t.sid AND cid='001') AS 企业管理 ,(SELECT score FROM SC WHERE SC.sid=t.sid AND cid='005') AS 英语 ,COUNT(*) AS 有效课程数, AVG(t.score) AS 平均成绩 FROM SC AS t GROUP BY sid ORDER BY avg(t.score)

18、查询各科成绩最高和最低的分:以如下形式显示:课程ID,最高分,最低分 select cid "课程ID",max(score) "最高分",min(score) "最低分" from sc group by cid

19、按各科平均成绩从低到高和及格率的百分数从高到低排序 oracle>

SELECT t.cid AS 课程号,MAX(course.Cname)AS 课程名,nvl(AVG(score),0) AS 平均成绩,100 * SUM(CASE WHEN nvl(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(*) AS 及格百分数

FROM SC T,Course

WHERE t.cid=course.cid

GROUP BY t.cid

ORDER BY 100 * SUM(CASE WHEN nvl(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(*) DESC

Mysql>

SELECT t.cid AS 课程号,MAX(course.Cname)AS 课程名,IFNULL(AVG(score),0) AS 平均成绩,100 * SUM(CASE WHEN IFNULL(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(*) AS 及格百分数

FROM SC T,Course

WHERE t.cid=course.cid

GROUP BY t.cid

ORDER BY 100 * SUM(CASE WHEN IFNULL(score,0)>=60 THEN 1 ELSE 0 END)/COUNT(*) DESC

20、查询如下课程平均成绩和及格率的百分数(用"1行"显示): 企业管理(001),马克思(002),OO&UML (003),数据库(004) SELECT SUM(CASE WHEN cid ='001' THEN score ELSE 0 END)/SUM(CASE cid WHEN '001' THEN 1 ELSE 0 END) AS 企业管理平均分 ,100 * SUM(CASE WHEN cid = '001' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN cid = '001' THEN 1 ELSE 0 END) AS 企业管理及格百分数 ,SUM(CASE WHEN cid = '002' THEN score ELSE 0 END)/SUM(CASE cid WHEN '002' THEN 1 ELSE 0 END) AS 马克思平均分 ,100 * SUM(CASE WHEN cid = '002' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN cid = '002' THEN 1 ELSE 0 END) AS 马克思及格百分数 ,SUM(CASE WHEN cid = '003' THEN score ELSE 0 END)/SUM(CASE cid WHEN '003' THEN 1 ELSE 0 END) AS UML平均分 ,100 * SUM(CASE WHEN cid = '003' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN cid = '003' THEN 1 ELSE 0 END) AS UML及格百分数 ,SUM(CASE WHEN cid = '004' THEN score ELSE 0 END)/SUM(CASE cid WHEN '004' THEN 1 ELSE 0 END) AS 数据库平均分 ,100 * SUM(CASE WHEN cid = '004' AND score >= 60 THEN 1 ELSE 0 END)/SUM(CASE WHEN cid = '004' THEN 1 ELSE 0 END) AS 数据库及格百分数 FROM SC

21、查询不同老师所教不同课程平均分从高到低显示 要求显示:教师ID,教师姓名,课程ID,课程名称,平均成绩 SELECT MAX(t.tid) "教师ID",MAX(t.tName) "教师姓名",c.cid "课程ID", MAX(c.cName) "课程名称" ,AVG(sc.score) "平均成绩"

FROM sc,course c,teacher t WHERE sc.cid = c.cid AND c.tid = t.tid GROUP BY c.tid,c.cid

ORDER BY AVG(sc.score) DESC

23、统计列印各科成绩,各分数段人数:课程ID,课程名称,[100-85],[85-70],[70-60],[ <60] SELECT SC.cid as 课程ID, Cname as 课程名称 ,SUM(CASE WHEN score BETWEEN 85 AND 100 THEN 1 ELSE 0 END) AS [100 - 85] ,SUM(CASE WHEN score BETWEEN 70 AND 85 THEN 1 ELSE 0 END) AS [85 - 70] ,SUM(CASE WHEN score BETWEEN 60 AND 70 THEN 1 ELSE 0 END) AS [70 - 60] ,SUM(CASE WHEN score < 60 THEN 1 ELSE 0 END) AS [60 -] FROM SC,Course where SC.cid=Course.cid GROUP BY SC.cid,Cname;

26、查询每门课程被选修的学生数 select cid,count(sid) from sc group by cid;

27、查询出只选修了一门课程的全部学生的学号和姓名 select SC.sid,Student.Sname,count(cid) AS 选课数 from SC ,Student where SC.sid=Student.sid group by SC.sid ,Student.Sname having count(cid)=1;

28、查询男生、女生人数 Select count(Ssex) as 男生人数 from Student group by Ssex having Ssex='男'; Select count(Ssex) as 女生人数 from Student group by Ssex having Ssex='女';

29、查询姓“张”的学生名单 SELECT Sname FROM Student WHERE Sname like '张%';

30、查询同名同性学生名单,并统计同名人数 SELECT sName,sSex ,COUNT(*) FROM student GROUP BY sName,sSex HAVING COUNT(*) > 1

31、1981年出生的学生名单(注:Student表中Sage列的类型是datetime)

Mysql> select Sname, CONVERT(char (11),DATEPART(year,Sage)) as age from student where CONVERT(char(11),DATEPART(year,Sage))='1981';

Oracle>

select * from student where substr(to_char(sage,'yyyy-MM-dd'),1,4)= '1981'

32、查询每门课程的平均成绩,结果按平均成绩升序排列,平均成绩相同时,按课程号降序排列 Select cid,Avg(score) from SC group by cid order by Avg(score),cid DESC ;

33、查询平均成绩大于85的所有学生的学号、姓名和平均成绩 select Sname,SC.sid ,avg(score) from Student,SC where Student.sid=SC.sid group by SC.sid,Sname having avg(score)>85;

34、查询课程名称为“数据库”,且分数低于60的学生姓名和分数 Select Sname,isnull(score,0) from Student,SC,Course where SC.sid=Student.sid and SC.cid=Course.cid and Course.Cname='数据库'and score <60;

35、查询所有学生的选课情况; SELECT SC.sid,SC.cid,Sname,Cname FROM SC,Student,Course where SC.sid=Student.sid and SC.cid=Course.cid ;

36、查询任何一门课程成绩在70分以上的姓名、课程名称和分数; SELECT distinct student.sid,student.Sname,SC.cid,SC.score FROM student,Sc WHERE SC.score>=70 AND SC.sid=student.sid;

37、查询不及格的课程,并按课程号从大到小排列 select cid from sc where scor e <60 order by cid ;

38、查询课程编号为003且课程成绩在80分以上的学生的学号和姓名; select SC.sid,Student.Sname from SC,Student where SC.sid=Student.sid and Score>80 and cid='003';

39、求选了课程的学生人数 select count(*) from sc;

40、查询选修“叶平”老师所授课程的学生中,成绩最高的学生姓名及其成绩 select Student.Sname,score from Student,SC,Course C,Teacher where Student.sid=SC.sid and SC.cid=C.cid and C.tid=Teacher.tid and Teacher.Tname='叶平' and SC.score=(select max(score)from SC where cid=C.cid );

41、查询各个课程及相应的选修人数 select count(*) from sc group by cid;

42、查询不同课程成绩相同的学生的学号、课程号、学生成绩 select distinct A.sid,B.score from SC A ,SC B where A.Score=B.Score and A.cid <>B.cid ;

43、查询每门功课成绩最好的前两名 SELECT *

FROM sc t1

WHERE (

SELECT COUNT(*)

FROM sc t2

WHERE t1.cid=t2.cid

AND t2.score>=t1.score

) <=2 ORDER BY t1.cid

44、统计每门课程的学生选修人数(超过10人的课程才统计)。要求输出课程号和选修人数,查询结果按人数降序排列,若人数相同,按课程号升序排列 SELECT cid "课程号",COUNT(*) "选修人数" FROM sc GROUP BY cid HAVING COUNT(*) >10 ORDER BY COUNT(*) DESC,cid

45、检索至少选修两门课程的学生学号 select sid from sc group by sid having count(*) > = 2

46、查询全部学生都选修的课程的课程号和课程名 SELECT s.sName,c.cName, COUNT(*) FROM student s,course c, sc WHERE s.sid = sc.sid AND sc.cid = c.cid GROUP BY sc.cid HAVING COUNT(*) = (SELECT COUNT(*) FROM student)

47、查询没学过“叶平”老师讲授的任一门课程的学生姓名 SELECT DISTINCT Sname FROM Student WHERE sid NOT IN (SELECT sid FROM Course,Teacher,SC WHERE Course.tid=Teacher.tid AND SC.cid=course.cid AND Tname='叶平');

48、查询两门以上不及格课程的同学的学号及其平均成绩 select sid,avg(ifnull(score,0)) from SC where sid in (select sid from SC where score <60 group by sid having count(*)>2)group by sid;

49、检索“004”课程分数小于60,按分数降序排列的同学学号 select sid from SC where cid='004'and score <60 order by score desc;

50、删除“1002”同学的“001”课程的成绩 delete from Sc where sid='1002' and cid='001';

行转列

CREATE TABLE stu_score (

grade_id varchar(10) DEFAULT NULL,

subject_name varchar(10) DEFAULT NULL,

max_score int(10) DEFAULT NULL

)

insert into `stu_score`(`grade_id`,`subject_name`,`max_score`) values('1','语文',98);

insert into `stu_score`(`grade_id`,`subject_name`,`max_score`) values('2','数学',95);

insert into `stu_score`(`grade_id`,`subject_name`,`max_score`) values('2','政治',87);

insert into `stu_score`(`grade_id`,`subject_name`,`max_score`) values('5','语文',97);

insert into `stu_score`(`grade_id`,`subject_name`,`max_score`) values('5','数学',100);

insert into `stu_score`(`grade_id`,`subject_name`,`max_score`) values('5','政治',92);

1.查询出要求的结果格式

SELECT

CASE grade_id WHEN 1 THEN '一年级'

WHEN 2 THEN '二年级'

WHEN 5 THEN '五年级'

END AS '年级',

CASE subject_name WHEN '语文' THEN max_score END AS '语文',

CASE subject_name WHEN '数学' THEN max_score END AS '数学',

CASE subject_name WHEN '政治' THEN max_score END AS '政治'

FROM stu_score

2,去除null

SELECT

CASE grade_id WHEN 1 THEN '一年级'

WHEN 2 THEN '二年级'

WHEN 5 THEN '五年级'

END AS '年级',

IFNULL(CASE subject_name WHEN '语文' THEN max_score END,0) AS '语文',

IFNULL(CASE subject_name WHEN '数学' THEN max_score END,0) AS '数学',

IFNULL(CASE subject_name WHEN '政治' THEN max_score END,0) AS '政治'

FROM stu_score

3.合并结果。

SELECT

CASE grade_id WHEN 1 THEN '一年级'

WHEN 2 THEN '二年级'

WHEN 5 THEN '五年级'

END AS '年级',

MAX(IFNULL(CASE subject_name WHEN '语文' THEN max_score END,0)) AS '语文',

MAX(IFNULL(CASE subject_name WHEN '数学' THEN max_score END,0)) AS '数学',

MAX(IFNULL(CASE subject_name WHEN '政治' THEN max_score END,0)) AS '政治'

FROM stu_score

GROUP BY grade_id

本文分享自微信公众号 - Java帮帮(javahelp),作者:奋斗蒙

原文出处及转载信息见文内详细说明,如有侵权,请联系 yunjia_community@tencent.com 删除。

原始发表时间:2017-10-06

本文参与腾讯云自媒体分享计划,欢迎正在阅读的你也加入,一起分享。

我来说两句

0 条评论
登录 后参与评论

相关文章

  • JSP与EL表达式重点学习笔记(1)

    Jsp&el表达式 JSP指令 ? JSP指令概述 JSP指令的格式:<%@指令名 attr1=”” attr2=”” %>,一般都会把JSP指令放到JSP文件...

    Java帮帮
  • Web-第四天 jQuery学习

    jQuery是一个JavaScript框架。它兼容CSS3,还兼容各种浏览器。文档说明很全,应用详细,成熟插件多。

    Java帮帮
  • 【数据库】MySQL进阶七、limit用法& varchar类型排序

    【数据库】MySQL进阶七、 limit用法与varchar排序 limit用法 limit是mysql的语法 select * from table limi...

    Java帮帮
  • SQL笔试50题(下)

    阅读原文,或者访问该链接可以在线观看(该系列将更新至GitHub,并且托管到read the docs)

    fireWang
  • 基于开源软件的云计算中有大量的创新机会

    近来在云计算领域,国内、国际大佬们的频频降价惊呆了一众小伙伴。3月份阿里、谷歌相继降价,4月1日起亚马逊降价,不知是否感受到了压力,微软日前宣布从5月1日起开始...

    静一
  • 【推荐】用数据创造商业价值

    GrowingIO联合创始人、CEO, 前LinkedIn美国商业分析部高级总监,张溪梦应邀参加7牛D-Furure 数据时代峰会,发表主题为《用数据分析创造...

    小莹莹
  • 用数据创造商业价值

    用户1756920
  • 纽约蹭饭手册:怎样利用Python和自动化脚本在纽约吃霸王餐?

    在家做饭不下馆子可以减少开支已经是公开的秘密。但作为一名美食天堂的国民,不下馆子几乎是不可能的。

    CDA数据分析师
  • 以太坊联合创始人:加密货币市场将会重新洗牌

    腾讯科技讯 据外媒报道,以太坊公司前首席执行官兼联合创始人查尔斯-霍斯金森(Charles Hoskinson)称,在比特币替代者价格崩溃后,加密货币市场将会出...

    企鹅号小编
  • 纽约蹭饭手册:怎样利用Python和自动化脚本在纽约吃霸王餐?

    在家做饭不下馆子可以减少开支已经是公开的秘密。但作为一名美食天堂的国民,不下馆子几乎是不可能的。

    大数据文摘

扫码关注云+社区

领取腾讯云代金券