A. The main query executes with the first value returned by the subquery.
B. The main query executes with the last value returned by the subquery.
C. The main query executes with all the values returned by the subquery.
D. The main query fails because the multiple-row subquery cannot be used with the comparison operator.
E. You cannot define a multiple-row subquery in the WHERE clause of a SQL query.
您可能感兴趣的试卷
你可能感兴趣的试题
A SELECT statement can be used to perform these three functions:
1. Choose rows from a table.
2. Choose columns from a table
3. Bring together data that is stored in different tables by creating a link between them.
Which set of keywords describes these capabilities?()
A. difference, projection, join
B. selection, projection, join
C. selection, intersection, join
D. intersection, projection, join
E. difference, projection, product
A. Constraints provide data independence.
B. Constraints make complex queries easy.
C. Constraints enforce rules at the view level.
D. Constraints enforce rules at the table level.
E. Constraints prevent the deletion of a table if there are dependencies.
F. Constraints prevent the deletion of an index if there are dependencies.
A. CREATE TABLE EMP9$# AS (empid number(2));
B. CREATE TABLE EMP*123 AS (empid number(2));
C. CREATE TABLE PACKAGE AS (packid number(2));
D. CREATE TABLE 1EMP_TEST AS (empid number(2));
A. TRIM
B. REPLACE
C. TRUNC
D. TO_DATE
E. MOD
F. CASE
A. A MERGE statement is used to merge the data of one table with data from another.
B. A MERGE statement replaces the data of one table with that of another.
C. A MERGE statement can be used to insert new rows into a table.
D. A MERGE statement can be used to update existing rows in a table.
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
A. The UNIQUE constraint does not permit a null value for the column.
B. A UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints.
C. The PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index.
D. The NOT NULL constraint ensures that null values are not permitted for the column.
A. It releases the storage space used by the table.
B. It does not release the storage space used by the table.
C. You can roll back the deletion of rows after the statement executes.
D. You can NOT roll back the deletion of rows after the statement executes.
E. An attempt to use DESCRIBE on the DEPT table after the TRUNCATE statement executes will display an error.
F. You must be the owner of the table or have DELETE ANY TABLE system privileges to truncate the DEPT table
You need to perform certain data manipulation operations through a view called EMP_DEPT_VU, which you previously created. You want to look at the definition of the view (the SELECT statement on which the view was create.)
How do you obtain the definition of the view?()
A. Use the DESCRIBE command in the EMP_DEPT VU view.
B. Use the DEFINE VIEW command on the EMP_DEPT VU view.
C. Use the DESCRIBE VIEW command on the EMP_DEPT VU view.
D. Query the USER_VIEWS data dictionary view to search for the EMP_DEPT_VU view.
E. Query the USER_SOURCE data dictionary view to search for the EMP_DEPT_VU view.
F. Query the USER_OBJECTS data dictionary view to search for the EMP_DEPT_VU view.
You need to design a student registration database that contains several tables storing academic information.
The STUDENTS table stores information about a student. The STUDENT_GRADES table stores information about the student's grades. Both of the tables have a column named STUDENT_ID. The STUDENT_ID column in the STUDENTS table is a primary key.
You need to create a foreign key on the STUDENT_ID column of the STUDENT_GRADES table that points to the STUDENT_ID column of the STUDENTS table. Which statement creates the foreign key?()
A. CREATE TABLE student_grades (student_id NUMBER(12),semester_end DATE, gpa NUMBER(4,3), CONSTRAINT student_id_fk REFERENCES (student_id) FOREIGN KEY student (student_id));
B. CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa NUMBER(4,3), student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id));
C. CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa NUMBER(4,3), CONSTRAINT FOREIGN KEY (student_id) REFERENCES student (student_id));
D. CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa NUMBER(4,3), CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id));
最新试题
The PRODUCTS table has these columns:PRODUCT_ID NUMBER(4)PRODUCT_NAME VARCHAR2(45)PRICE NUMBER(8,2)Evaluate this SQL statement:SELECT *FROM PRODUCTSORDER BY price, product _ name;What is true about the SQL statement? ()
Examine the statement: Create synonym emp for hr. employees; What happens when you issue the statement? ()
Which three statements about subqueries are true? ()
Evaluate these two SQL statements: SELECT last_name, salary, hire_dateFROM EMPLOYEES ORDRE BY salary DESC; SELECT last_name, salary, hire_dateFROM EMPOLYEES ORDER BY 2 DESC; What is true about them? ()
Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary KeyFIRST_NAME VARCHAR2 (25)LAST_NAME VARCHAR2 (25)HIRE_DATE DATEWhich UPDATE statement is valid? ()
For which action can you use the TO_DATE function? ()
Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER Primary KeyFIRST_NAME VARCHAR2(25)LAST_NAME VARCHAR2(25)HIRE_DATE DATEWhich INSERT statement is valid? ()
You need to perform these tasks:1. Create and assign a MANAGER role to Blake and Clark2. Grant CREATE TABLE and CREATE VIEW privileges to Blake and ClarkWhich set of SQL statements achieves the desired results? ()
Which view should a user query to display the columns associated with the constraints on a table owned by the user? ()
Examine the structure of the STUDENTS table:STUDENT_ID NUMBER NOT NULL, Primary KeySTUDENT_NAME VARCHAR2(30)COURSE_ID VARCHAR2(10) NOT NULLMARKS NUMBERSTART_DATE DATEFINISH_DATE DATEYou need to create a report of the 10 students who achieved the highest ranking in the course INT SQL and who completed the course in the year 1999.Which SQL statement accomplishes this task? ()