[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$fX9KU0ShLsYG5qgu9bNiWGXEeiLMNJ0kvh4UC4I5WAEc":3},{"answer":4,"createTime":5,"id":6,"options":7,"origin":12,"question":16,"related":17,"source":21,"type":22},[],"2026-05-20 09:32:30",378715694,[8,9,10,11],"<all dname<>'Sales'","<any dname<>'Sales'",">any dname='Sales'",">all dname='Sales'",{"courseId":13,"courseImg":14,"courseName":15},"53e1d2ef4961cca8eea3e23969ad2cb9","https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F03a579384a6dc297c89809b582fcc767.png","默认课程","某企业人事管理系统中有如下关系模式:员工表Emp(eno,ename,age,sal,dname),其中的属性分别表示员工号、员工姓名、年龄、工资和部门名称;部门表Dept(dname,phone),其中的属性分别表示部门名称和联系电话.现需要查询其他部门比销售部门(Sales)所有员工年龄都要小的员工姓名及年龄,对应的SQL 语句如下: select ename, age from Emp where age 【空白】 (select age from Emp where dname=' Sales' ) and 【空白】 ; 上面SQL语句中留空处的答案为以下哪个",[18,23,32,41,50,59,68,77,89,100],{"answer":19,"createTime":5,"id":6,"options":20,"question":16,"source":21,"type":22},[],[8,9,10,11],"v1",0,{"answer":24,"createTime":5,"id":25,"options":26,"question":31,"source":21,"type":22},[],378715696,[27,28,29,30],"程序的逻辑独立性","数据的逻辑独立性","数据的物理独立性","程序的物理独立性","在数据库系统运行维护阶段,通过重建视图能够实现( )",{"answer":33,"createTime":5,"id":34,"options":35,"question":40,"source":21,"type":22},[],378715698,[36,37,38,39],"select A,B,D from R natural join S","select A,B,D from R,S where R.C=S.C","select A, B, D from R inner join S on R.C=S.C","select A,B,D from R full outer join S on R.C=S.C","设有关系R(A,B,C)和S(C,D),与关系代数表达式\u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002Fc73567bcff81d19ffe19733661c5803e.png\">不等价的SQL语句是哪个",{"answer":42,"createTime":5,"id":43,"options":44,"question":49,"source":21,"type":22},[],378715700,[45,46,47,48],"子查询返回的是布尔值","子查询返回的是多个值","子查询返回的是单个值","子查询不返回值","在嵌套查询中,用>、<、=>、=<、=、<>等比较运算符引出子查询的条件是什么",{"answer":51,"createTime":5,"id":52,"options":53,"question":58,"source":21,"type":22},[],378715704,[54,55,56,57],"order by子句","where子句","having子句","group by子句","对分组查询结果进行筛选的是( ),其条件表达式中可以使用集函数",{"answer":60,"createTime":5,"id":61,"options":62,"question":67,"source":21,"type":22},[],378715707,[63,64,65,66],"自动更新基表统计信息","启用视图缓存优化","阻止插入不符合视图条件的数据","强制使用索引查询","创建视图时使用WITH CHECK OPTION的作用是什么",{"answer":69,"createTime":5,"id":70,"options":71,"question":76,"source":21,"type":22},[],378715710,[72,73,74,75],"检索、插入、修改和删除功能","模式定义功能","外模式定义功能","数据库的完整性定义功能","DBMS提供的DDL功能不包括( )",{"answer":78,"createTime":5,"id":79,"options":80,"question":87,"source":21,"type":88},[],378715713,[81,82,83,84,85,86],"视图中的数据只能来自一张基本表","视图中的数据也会存放在数据库中","对视图的更新最终转换为对基本表的更新","数据库中只存放视图的定义","视图不可以更新","视图可以从视图中导出","下列关于视图的描述中正确的是哪几个",1,{"answer":90,"createTime":5,"id":91,"options":92,"question":99,"source":21,"type":88},[],378715716,[93,94,95,96,97,98],"where子句的作用对象是分组结果","where子句的作用对象是基本表或视图","having子句的作用对象是分组结果","having子句必须跟在group by子句之后,如果没有group by子句就不能有having子句","having子句的作用对象是基本表或者视图","where子句和having子句不能同时出现","下列关于where子句和having子句的描述中,错误的是哪几个",{"answer":101,"createTime":5,"id":102,"options":103,"question":109,"source":21,"type":88},[],378715718,[104,105,106,107,108],"表的实体完整性约束","表上建立的索引","uniqe、check、not null等约束","表上建立的视图","表中的数据","在Oracle中一个基本表的定义一旦被删除,则与此基本表相关的哪些内容或对象也被自动被删除"]