皮皮学，免费搜题
登录
搜题
【简答题】
为防止起动时产生电流冲击,在单闭环调速系统中须加 环节。
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
.
..
皮皮学刷刷变学霸
举一反三
【简答题】Henry had studied in a university before he came back to his hometown. He thought he had lots of knowledge and he was supercilious(目中无人). At first he was easily given a job in a bank. But he couldn,t ...
查看完整题目与答案
【简答题】B. Rewrite the following sentences after the models, using the structure “remember doing something” or “remember to do something”, according to the meaning of the sentence. Model 1: Do you remember th...
查看完整题目与答案
【简答题】Many people believe Henry Ford invented the automobile (汽车). But Henry Ford did not start to build his first car until 1896. That was eleven years after two Germans developed the world's first automob...
查看完整题目与答案
【单选题】下列关于触发器优点的描述,错误的是( )
A.
触发器是自动执行的
B.
触发器可以实现对数据库中的相关表的级联更改
C.
强化完整性约束
D.
提高数据的检索速度
查看完整题目与答案
【多选题】关于剥脱苔主病,下面描述正确的是:()
A.
主胃气不足
B.
主气血两虚
C.
主阴虚重证
D.
主痰浊
E.
预后不良
查看完整题目与答案
【单选题】—Could you tell me _________? — You can take No. 16 bus.
A.
how can we get to the Olympic Park
B.
how we can get to the Olympic Park
C.
how did we get to the Olympic Park
D.
how we got to the Olympic Park
查看完整题目与答案
【单选题】下列关于触发器的描述中错误的是
A.
REPLACE语句不能被DELETE触发器激活
B.
每个数据表最多支持6个触发器
C.
BEFORE INSERT触发器不仅能被INSERT语句激活,也能被LOAD DATA语句激活
D.
一个数据表不能同时定义两个BEFORE UPDATE触发器
查看完整题目与答案
【简答题】Revising: Shifts in subject and voice Make the following sentences consistent in subject and voice. Example: At the reunion they ate hot dogs and volleyball was played. At the reunion they ate hot dog...
查看完整题目与答案
【判断题】在删除关系表中数据时,要先删除主表数据再删除从表数据
A.
正确
B.
错误
查看完整题目与答案
【单选题】下列关于触发器描述错误的是( )。
A.
一个表在相同的触发事件和相同的触发时间只能创建一个触发器。
B.
触发事件为INSERT,触发时间为AFTER的触发器只能有一个
C.
一个表在相同的触发事件上可以创建两个触发器
D.
触发器可以显示调用
查看完整题目与答案
相关题目：
【简答题】Henry had studied in a university before he came back to his hometown. He thought he had lots of knowledge and he was supercilious(目中无人). At first he was easily given a job in a bank. But he couldn,t ...
查看完整题目与答案
【简答题】B. Rewrite the following sentences after the models, using the structure “remember doing something” or “remember to do something”, according to the meaning of the sentence. Model 1: Do you remember th...
查看完整题目与答案
【简答题】Many people believe Henry Ford invented the automobile (汽车). But Henry Ford did not start to build his first car until 1896. That was eleven years after two Germans developed the world's first automob...
查看完整题目与答案
【单选题】下列关于触发器优点的描述,错误的是( )
A.
触发器是自动执行的
B.
触发器可以实现对数据库中的相关表的级联更改
C.
强化完整性约束
D.
提高数据的检索速度
查看完整题目与答案
【多选题】关于剥脱苔主病,下面描述正确的是:()
A.
主胃气不足
B.
主气血两虚
C.
主阴虚重证
D.
主痰浊
E.
预后不良
查看完整题目与答案
【单选题】—Could you tell me _________? — You can take No. 16 bus.
A.
how can we get to the Olympic Park
B.
how we can get to the Olympic Park
C.
how did we get to the Olympic Park
D.
how we got to the Olympic Park
查看完整题目与答案
【单选题】下列关于触发器的描述中错误的是
A.
REPLACE语句不能被DELETE触发器激活
B.
每个数据表最多支持6个触发器
C.
BEFORE INSERT触发器不仅能被INSERT语句激活,也能被LOAD DATA语句激活
D.
一个数据表不能同时定义两个BEFORE UPDATE触发器
查看完整题目与答案
【简答题】Revising: Shifts in subject and voice Make the following sentences consistent in subject and voice. Example: At the reunion they ate hot dogs and volleyball was played. At the reunion they ate hot dog...
查看完整题目与答案
【判断题】在删除关系表中数据时,要先删除主表数据再删除从表数据
A.
正确
B.
错误
查看完整题目与答案
【单选题】下列关于触发器描述错误的是( )。
A.
一个表在相同的触发事件和相同的触发时间只能创建一个触发器。
B.
触发事件为INSERT,触发时间为AFTER的触发器只能有一个
C.
一个表在相同的触发事件上可以创建两个触发器
D.
触发器可以显示调用
查看完整题目与答案