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单选题
Which statement explicitly names a constraint?（）
A
ALTER TABLE student_grades ADD FOREIGN KEY (student_id) REFERENCES students(student_id);
B
ALTER TABLE student_grades ADD CONSTRAINT NAME = student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id);
C
ALTER TABLE student_grades ADD CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id);
D
ALTER TABLE student grades ADD NAMED CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id);
E
ALTER TABLE student grades ADD NAME student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id);
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更多 “单选题Which statement explicitly names a constraint?（）A ALTER TABLE student_grades ADD FOREIGN KEY (student_id) REFERENCES students(student_id);B ALTER TABLE student_grades ADD CONSTRAINT NAME = student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id);C ALTER TABLE student_grades ADD CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id);D ALTER TABLE student grades ADD NAMED CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id);E ALTER TABLE student grades ADD NAME student_id_fk FOREIGN KEY (student_id) REFERENCES students(student_id);” 相关考题
考题
Which statement adds a constraint that ensures the CUSTOMER_NAME column of the CUSTOMERS table holds a value?()
A. ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;B. ALTER TABLE customers MODIFY CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;C. ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn NOT NULL;D. ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn IS NOT NULL;E. ALTER TABLE customers MODIFY name CONSTRAINT cust_name_nn NOT NULL;F. ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name NOT NULL;
考题
Which statement explicitly names a constraint? ()
A. ALTER TABLE student_grades ADD FOREIGN KEY (student_id) REFERENCES students (student_id);B. ALTER TABLE student_grades ADD CONSTRAINT NAME = student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);C. ALTER TABLE student_grades ADD CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);D. ALTER TABLE student grades ADD NAMED CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);E. ALTER TABLE student grades ADD NAME student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);
考题
When defining a referential constraint between the parent table T2 and the dependent table T1, which of the following is true?()
A.The list of column names in the FOREIGN KEY clause can be a subset of the list of column names in the primary key of T2 or a UNIQUE constraint that exists on T2.B.The list of column names in the FOREIGN KEY clause can be a subset of the list of column names in the primary key of T1 or a UNIQUE constraint that exists on T1.C.The list of column names in the FOREIGN KEY clause must be identical to the list of column names in the primary key of T2 or a UNIQUE constraint that exists on T2.D.The list of column names in the FOREIGN KEY clause must be identical to the list of column names in the primary key of T1 or a UNIQUE constraint that exists on T1.
考题
Which of the following is true of an index used to support a UNIQUE constraint?()
A.It must have the UNIQUE attribute.B.It cannot be created explicitly by the user.C.It must have the UNIQUE and CLUSTER attributes.D.It must have the UNIQUE WHERE NOT NULL attribute.
考题
In which of the following situations should correlation names be used?（）A、A table referenced in the FROM clause has no indexed column.B、The table referenced in the FROM clause has more than 200 columns.C、Two or more tables in the FROM clause have identical column names.D、The FROM clause contains two or more tables in the SELECT statement.
考题
Which two statements about views are true? （）A、A view can be created as read only.B、A view can be created as a join on two or more tables.C、A view cannot have an ORDER BY clause in the SELECT statement.D、A view cannot be created with a GROUP BY clause in the SELECT statement.E、A view must have aliases defined for the column names in the SELECT statement.
考题
Evaluate the CREATE TABLE statement： CREATE TABLE products （product_id NUMBER （6） CONSTRAINT prod_id_pk PRIMARY KEY， product_name VARCHAR2 （15））； Which statement is true regarding the PROD_ID_PK constraint？（）A、 It would be created only if a unique index is manually created first.B、 It would be created and would use an automatically created unique index.C、 It would be created and would use an automatically created nonunique index.D、 It would be created and remains in a disabled state because no index is specified in the command.
考题
View the Exhibit to observe the roles assigned to the SL_REP user. Which statement is true about theassignment of the SELECT_CATALOG_ROLE role to the SL_REP user（）A、The user must enable the role explicitly.B、The user can grant the role to other users.C、The user cannot use the role until the DBA enables it explicitly.D、The user can start using the role immediately without any changes
考题
Which two statements are true regarding the ORDER BY clause? （）A、It is executed first in the query execution B、It must be the last clause in the SELECT statement C、It cannot be used in a SELECT statement containing a HAVING clauseD、You cannot specify a column name followed by an expression in this clause E、You can specify a combination of numeric positions and column names in this clause
考题
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);
考题
Which statement is true？（）A、A class’s finalize（） method CANNOT be invoked explicitly.B、super.finalize（） is called implicitly by any overriding finalize（） method.C、The finalize（） method for a given object is called no more than once by the garbage collector.D、The order in which finalize（） is called on two objects is based on the order in which the two objects became finalizable.
考题
Which is an example of a dynamic SELECT statement? （）A、A query whose object names change during its execution. B、A query whose object names are not known until run time. C、A query whose bind variables values change during execution. D、A query whose bind variable values are not known until run time.
考题
Examine the following statement that is used to modify the constraint on the SALES table： SQL ALTER TABLE SALES MODIFY CONSTRAINT pk DISABLE VALIDATE； Which three statements are true regarding the above command（）A、The constraint remains valid.B、The index on the constraint is dropped.C、It allows the loading of data into the table using SQL*Loader.D、New data conforms to the constraint， but existing data is not checkedE、It allows the data manipulation on the table using INSERT/UPDATE/DELETE SQL statements.
考题
Which two statements about creating constraints are true?（）A、Constraint names must start with SYS_CB、All constraints must be defines at the column levelC、Constraints can be created after the table is createdD、Constraints can be created at the same time the table is createdE、Information about constraints is found in the VIEW_CONSTRAINTS dictionary view
考题
You need to design the restrictions on the Bank.Customers table. Which three actions should you perform?（）A、Design a trigger that verifies that the first names and surnames are not empty strings.B、Design a check constraint that verifies that the first names and surnames are not empty strings.C、Design a check constraint that uses a CLR user-defined function to verify that either the phone number is a null value or the format of the phone number is valid.D、Design a trigger that uses a CLR user-defined function to verify that either the phone number is a null value or the format of the phone number is valid.E、Design a check constraint that ensures that the phone number cannot be changed from a valid format to a null value or to an invalid format.F、Design a trigger that ensures that the phone number cannot be changed from a valid format to a null value.
考题
Which of the following is true of an index used to support a UNIQUE constraint?（）A、It must have the UNIQUE attribute.B、It cannot be created explicitly by the user.C、It must have the UNIQUE and CLUSTER attributes.D、It must have the UNIQUE WHERE NOT NULL attribute.
考题
多选题Examine the following statement that is used to modify the primary key constraint on the SALES table： SQL ALTER TABLE SALES MODIFY CONSTRAINT pk DISABLE VALIDATE； Which three statements aretrue regarding the above command（）AThe constraint remains valid.BThe index on the constraint is dropped.CIt allows the loading of data into the table using SQL *Loader.DNew data conforms to the constraint， but existing data is not checked.EIt allows the data manipulation on the table using INSERT/UPDATE/DELETE SQL statements.
考题
单选题Which of the following is true of an index used to support a UNIQUE constraint?（）A
It must have the UNIQUE attribute.B
It cannot be created explicitly by the user.C
It must have the UNIQUE and CLUSTER attributes.D
It must have the UNIQUE WHERE NOT NULL attribute.
考题
单选题View the Exhibit to observe the roles assigned to the SL_REP user. Which statement is true about theassignment of the SELECT_CATALOG_ROLE role to the SL_REP user（）A
The user must enable the role explicitly.B
The user can grant the role to other users.C
The user cannot use the role until the DBA enables it explicitly.D
The user can start using the role immediately without any changes
考题
单选题Which statement is true？（）A
A class’s finalize（） method CANNOT be invoked explicitly.B
super.finalize（） is called implicitly by any overriding finalize（） method.C
The finalize（） method for a given object is called no more than once by the garbage collector.D
The order in which finalize（） is called on two objects is based on the order in which the two objects became finalizable.
考题
多选题Examine the following statement that is used to modify the constraint on the SALES table： SQL ALTER TABLE SALES MODIFY CONSTRAINT pk DISABLE VALIDATE； Which three statements are true regarding the above command（）AThe constraint remains valid.BThe index on the constraint is dropped.CIt allows the loading of data into the table using SQL*Loader.DNew data conforms to the constraint， but existing data is not checkedEIt allows the data manipulation on the table using INSERT/UPDATE/DELETE SQL statements.
考题
单选题Which statement explicitly names a constraint?（）A
ALTER TABLE student_grades ADD FOREIGN KEY (student_id) REFERENCES students (student_id);B
ALTER TABLE student_grades ADD CONSTRAINT NAME = student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);C
ALTER TABLE student_grades ADD CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);D
ALTER TABLE student grades ADD NAMED CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);E
ALTER TABLE student grades ADD NAME student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);
考题
多选题Which two statements about views are true?（）AA view can be created as read only.BA view can be created as a join on two or more tables.CA view cannot have an ORDER BY clause in the SELECT statement.DA view cannot be created with a GROUP BY clause in the SELECT statement.EA view must have aliases defined for the column names in the SELECT statement.
考题
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);
考题
单选题Evaluate the CREATE TABLE statement： CREATE TABLE products （product_id NUMBER （6） CONSTRAINT prod_id_pk PRIMARY KEY， product_name VARCHAR2 （15））； Which statement is true regarding the PROD_ID_PK constraint？（）A
It would be created only if a unique index is manually created first.B
It would be created and would use an automatically created unique index.C
It would be created and would use an automatically created nonunique index.D
It would be created and remains in a disabled state because no index is specified in the command.
考题
单选题When defining a referential constraint between the parent table T2 and the dependent table T1, which of the following is true?（）A
The list of column names in the FOREIGN KEY clause can be a subset of the list of column names in the primary key of T2 or a UNIQUE constraint that exists on T2.B
The list of column names in the FOREIGN KEY clause can be a subset of the list of column names in the primary key of T1 or a UNIQUE constraint that exists on T1.C
The list of column names in the FOREIGN KEY clause must be identical to the list of column names in the primary key of T2 or a UNIQUE constraint that exists on T2.D
The list of column names in the FOREIGN KEY clause must be identical to the list of column names in the primary key of T1 or a UNIQUE constraint that exists on T1.
考题
单选题Which statement adds a constraint that ensures the CUSTOMER_NAME column of the CUSTOMERS table holds a value?（）A
ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;B
ALTER TABLE customers MODIFY CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;C
ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn NOT NULL;D
ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn IS NOT NULL;E
ALTER TABLE customers MODIFY name CONSTRAINT cust_name_nn NOT NULL;F
ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name NOT NULL;
考题
单选题Which is an example of a dynamic SELECT statement? （）A
A query whose object names change during its execution. B
A query whose object names are not known until run time. C
A query whose bind variables values change during execution. D
A query whose bind variable values are not known until run time.
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