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【简答题】
translate the following phrases remind sb of sth agree with feel sorry for oneself be full of expect sb to do something since then give up finish doing be active in out of school go on to do go on doing take it easy overcome difficulties not... until
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举一反三
【单选题】The empty statement is represented by placing __________ where a statement would normally be.
A.
empty
B.
;
C.
null
D.
:
【单选题】You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty.Which statement accomplishes this task?（）
A.
ALTER TABLE students ADD PRIMARY KEY _ id;
B.
ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);
C.
ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;
D.
ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
E.
ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
【单选题】使用 scanf( ) 和 printf( ) 函数时,必须在程序开头加上预处理命令 ( )。
A.
#include
B.
#include
C.
#include
D.
#include
【单选题】Given that the current directory is empty, and that the user has read and write permissions, and the following: Which statement is true?（）
A.
Compilation fails.
B.
The file system has a new empty directory named dir.
C.
The file system has a new empty directory named newDir.
D.
The file system has a directory named dir, containing a file f1.txt.
E.
The file system has a directory named newDir, containing a file f1.txt.
【单选题】Given that the current directory is empty, and that the user has read and write privileges to the current, and the following: Which statement is true?（）
A.
Compilation fails.
B.
Nothing is added to the file system.
C.
Only a new file is created on the file system.
D.
Only a new directory is created on the file system.
E.
Both a new file and a new directory are created on the file system.
【单选题】You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty.Which statement accomplishes this task?（）
A.
ALTER TABLE students ADD PRIMARY KEY student_id;
B.
ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student _ id);
C.
ALTER TABLE students ADD CONSTRAINT stud _ id _pk PRIMARY KEY (student _ id);
D.
ALTER TABLE students MODIFY CONSTRAINT stud _ id _pk PRIMARY KEY (student _ id);
【简答题】The report looks ________ (impression), but it’s really nothing but empty statement.
【简答题】The report looks ________ (impression), but it’s really nothing but empty statement.A. impressive
相关题目：
【单选题】使用 scanf( ) 和 printf( ) 函数时,必须在程序开头加上预处理命令 ( )。
A.
#include
B.
#include
C.
#include
D.
#include