Which SQL statement defines a FOREIGN KEY constraint on the DEPTNO column of the EMP table?（）A、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);B、CREATE

题目

Which SQL statement defines a FOREIGN KEY constraint on the DEPTNO column of the EMP table?（）

A、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);
B、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));
C、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));
D、CREATE TABLE EMP (empno NUMBER(4), ename VARCHAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));

参考答案和解析

正确答案:B

如果没有搜索结果或未解决您的问题，请直接联系老师获取答案。

相似问题和答案

第1题：

You run the SQL Tuning Advisor (STA) to tune a SQL statement that is part of a fixed SQL plan baseline. The STA generates a SQL profile for the SQL statement, which recommends that you accept the profile. Which statement is true when you accept the suggested SQL profile?（）

A. The tuned plan is not added to the SQL plan baseline.

B. The tuned plan is added to the fixed SQL plan baseline as a fixed plan.

C. The tuned plan is added to the fixed SQL plan baseline as a nonfixed plan.

D. The tuned plan is added to a new nonfixed SQL plan baseline as a nonfixed plan.

参考答案：C

第2题：

Evaluate this SQL statement:In the statement, which capabilities of a SELECT statement are performed?()

A. Selection, projection, join

B. Difference, projection, join

C. Selection, intersection, join

D. Intersection, projection, join

E. Difference, projection, product

参考答案：A

第3题：

Which of the following statements about ORACLE is (are) correct?

Ⅰ.ORACLE follows SQL standard

Ⅱ.ORACLE database defines two logical types: table and view

A．Ⅰonly

B．Ⅱ only

C．Ⅰ and Ⅱ

D．none of the above

正确答案：C

第4题：

Which three features work together, to allow a SQL statement to have different cursors for the samestatement based on different selectivity ranges?（）

A、Bind Variable Peeking
B、SQL Plan Baselines
C、Adaptive Cursor Sharing
D、Bind variable used in a SQL statement
E、Literals in a SQL statement

正确答案:A,C,E

第5题：

Which three features work together, to allow a SQL statement to have different cursors for the samestatement based on different selectivity ranges?()

A. Bind Variable Peeking

B. SQL Plan Baselines

C. Adaptive Cursor Sharing

D. Bind variable used in a SQL statement

E. Literals in a SQL statement

参考答案：A, C, E

第6题：

Which of the following cannot be used as input to the SQL Tuning Advisor?() (Choose all that apply.)

A. A single SQL statement provided by a user

B. An existing SQL Tuning Set (STS)

C. A preprocessed Database Replay workload

D. A schema name

E. SQL statement identified in EM as using excessive resources

参考答案：C, D

第7题：

Examine the structure of the EMPLOYEES and DEPARTMENTS tables:Evaluate this SQL statement:Which SQL statement is equivalent to the above SQL statement?()