题目内容

违约风险越高,投资收益率也应该越高。( )

A. 对
B. 错

查看答案

搜索结果不匹配？点我反馈

更多问题

附息债券是债券市场中最普遍、最具有代表性的债券。( )

A. 对
B. 错

#创建数据库create database lx;use lx;#创建数据表CREATE TABLE students(sno VARCHAR(3) ,sname VARCHAR(4) NOT NULL,ssex VARCHAR(2) NOT NULL,sbirthday DATETIME,class VARCHAR(5));CREATE TABLE courses(cno VARCHAR(5),cname VARCHAR(10) NOT NULL,tno VARCHAR(10) NOT NULL);CREATE TABLE scores(sno VARCHAR(3) ,cno VARCHAR(5) NOT NULL,degree decimal(10, 1) NOT NULL);CREATE TABLE teachers(tno VARCHAR(3) ,tname VARCHAR(4) NOT NULL, tsex VARCHAR(2) NOT NULL,tbirthday DATETIME NOT NULL, prof VARCHAR(6),depart VARCHAR(10) NOT NULL);#插入数据INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (108 ,'曾华' ,'男' ,'1977-09-01',95033);INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (105 ,'匡明' ,'男' ,'1975-10-02',95031);INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (107 ,'王丽' ,'女' ,'1976-01-23',95033);INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (101 ,'李军' ,'男' ,'1976-02-20',95033);INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (109 ,'王芳' ,'女' ,'1975-02-10',95031);INSERT INTO STUDENTS (SNO,SNAME,SSEX,SBIRTHDAY,CLASS) VALUES (103 ,'陆君' ,'男' ,'1974-06-03',95031);INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('3-105' ,'计算机导论',825);INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('3-245' ,'操作系统' ,804);INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('6-166' ,'数字电路' ,856);INSERT INTO COURSES(CNO,CNAME,TNO)VALUES ('9-888' ,'高等数学' ,100);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (103,'3-245',86);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (105,'3-245',75);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (109,'3-245',68);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (103,'3-105',92);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (105,'3-105',88);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (109,'3-105',76);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (101,'3-105',64);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (107,'3-105',91);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (108,'3-105',78);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (101,'6-166',85);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (107,'6-106',79);INSERT INTO SCORES(SNO,CNO,DEGREE)VALUES (108,'6-166',81);INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (804,'李诚','男','1958-12-02','副教授','计算机系');INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (856,'张旭','男','1969-03-12','讲师','电子工程系');INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (825,'王萍','女','1972-05-05','助教','计算机系');INSERT INTO TEACHERS(TNO,TNAME,TSEX,TBIRTHDAY,PROF,DEPART) VALUES (831,'刘冰','女','1977-08-14','助教','电子工程系');简单描述上面的sql命令完成了什么操作？

查询Student表中的所有记录的Sname、Ssex和Class列。

查询教师所有的单位即不重复的Depart列