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（）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 checked.E、It allows the data manipulation on the table using INSERT/UPDATE/DELETE SQL statements.
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（）
- 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 checked.
- E、It allows the data manipulation on the table using INSERT/UPDATE/DELETE SQL statements.
相关考题：
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 _ 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);
Which syntax turns an existing constraint on? () A. ALTER TABLE table_name ENABLE constraint_name;B. ALTER TABLE table_name STATUS = ENABLE CONSTRAINT constraint _ name;C. ALTER TABLE table_name ENABLE CONSTRAINT constraint _ name;D. ALTER TABLE table_name TURN ON CONSTRAINT constraint _ name;
为表TEST中ID列添加主键约束的语法是（）A、ALTER TABLE TEST CHANGE（ ID INT PRIMARY KEY）B、ALTER TABLE TEST ADD（ ID INT PRIMARY KEY）C、ALTER TABLE TEST MODIFY（ ID INT PRIMARY KEY）D、ALTER TABLE TEST ADD CONSTRAINT PK PRIMARY KEY （ID）
删除PRIMARYKEY约束条件及其所有依赖约束条件的语法是什么（）A、ALTER TABLE table_name DROP CONSTRAINT constraint_name CASCADEB、ALTER TABLE table_name DROP CONSTRAINT FOREIGN KEY CASCADEC、DROP CONSTRAINT table_name（constraint_name）D、ALTER TABLE table_name DROP CONSTRAINT constraint_name
Which syntax turns an existing constraint on?（）A、ALTER TABLE table_name ENABLE constraint_name;B、ALTER TABLE table_name STATUS = ENABLE CONSTRAINT constraint_name;C、ALTER TABLE table_name ENABLE CONSTRAINT constraint_name;D、ALTER TABLE table_name STATUS ENABLE CONSTRAINT constraint_name;E、ALTER TABLE table_name TURN ON CONSTRAINT constraint_name;
A constraint in a table is defined with the INITIALLY IMMEDIATE clause. You executed the ALTER TABLEcommand with the ENABLE VALIDATE option to enable the constraint that was disabled. What are the twoeffects of this command（）A、It fails if any existing row violates the constraint.B、It does not validate the existing data in the table.C、It enables the constraint to be enforced at the end of each transaction.D、It prevents insert， update， and delete operations on the table while the constraint is in the process of beingenabled
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.
Which two statements are true about the primary key constraint in a table？ （）A、It is not possible to disable the primary key constraint.B、It is possible to have more than one primary key constraint in a single table.C、The primary key constraint can be referred by only one foreign key constraint.D、The primary key constraint can be imposed by combining more than one column.E、The non-deferrable primary key constraint creates an unique index on the primary key column if it is not already indexed.
Which syntax turns an existing constraint on?（）A、ALTER TABLE table_name ENABLE constraint_name;B、ALTER TABLE table_name STATUS = ENABLE CONSTRAINT constraint _ name;C、ALTER TABLE table_name ENABLE CONSTRAINT constraint _ name;D、ALTER TABLE table_name TURN ON CONSTRAINT constraint _ name;
You just issued the following statement: ALTER TABLE SALES DROP COLUMN PROFIT. Which of the following choices identifies when the column will actually be removed from Oracle?（）A、Immediately following statement execution B、After the ALTER TABLE DROP UNUSED COLUMNS command is issued C、After the ALTER TABLE SET UNUSED COLUMN command is issued D、After the ALTER TABLE MODIFY command is issued
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;
Examine the command that is used to create a table： SQL CREATE TABLE orders（oid NUMBER（6） PRIMARY KEY， odate DATE， ccode NUMBER（6）， oamt NUMBER（10，2）） TABLESPACE users； Which two statements are true about the effect of the above command） （）A、A CHECK constraint is created on the OID column.B、A NOT NULL constraint is created on the OID column.C、The ORDERS table is the only object created in the USERS tablespace.D、The ORDERS table and a unique index are created in the USERS tablespace.E、The ORDERS table is created in the USERS tablespace and a unique index is created on the OIDcolumn in the SYSTEM tablespace.
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);
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);
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.
多选题Examine the command that is used to create a table： SQL CREATE TABLE orders（oid NUMBER（6） PRIMARY KEY， odate DATE， ccode NUMBER （6）， oamtNUMBER（10，2）） TABLESPACE users； Which two statements are true about the effect of the above command（）AA CHECK constraint is created on the OID column.BA NOT NULL constraint is created on the OID column.CThe ORDERS table is the only object created in the USERS tablespace.DThe ORDERS table and a unique index are created in the USERS tablespace.EThe ORDERS table is created in the USERS tablespace and a unique index is created on the OID columnin the SYSTEM tablespace.
多选题A constraint in a table is defined with the INITIALLY IMMEDIATE clause. You executed the ALTER TABLEcommand with the ENABLE VALIDATE option to enable the constraint that was disabled. What are the twoeffects of this command（）AIt fails if any existing row violates the constraint.BIt does not validate the existing data in the table.CIt enables the constraint to be enforced at the end of each transaction.DIt prevents insert， update， and delete operations on the table while the constraint is in the process of beingenabled
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.
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?（）AALTER TABLE students ADD PRIMARY KEY _ id;BALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);CALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;DALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);EALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
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.
单选题View the Exhibit and examine the structure of the EMP table. You executed the following command to add a primary key to the EMP table： ALTER TABLE emp ADD CONSTRAINT emp_id_pk PRIMARY KEY （emp_id） USING INDEX emp_id_idx； Which statement is true regarding the effect of the command？（）A The PRIMARY KEY is created along with a new index.B The PRIMARY KEY is created and it would use an existing unique index.C The PRIMARY KEY would be created in a disabled state because it is using an existing index.D The statement produces an error because the USING clause is permitted only in the CREATE TABLE command.
多选题A constraint in a table is defined with the INITIALLY IMMEDIATE clause. You executed the ALTER TABLE command with the ENABLE VALIDATE option to enable the constraint that was disabled. What are the two effects of this command？（）AIt fails if any existing row violates the constraint.BIt does not validate the existing data in the table.CIt enables the constraint to be enforced at the end of each transaction.DIt prevents insert， update， and delete operations on the table while the constraint is in the process of being enabled.
多选题Which two statements are true about the primary key constraint in a table？ （）AIt is not possible to disable the primary key constraint.BIt is possible to have more than one primary key constraint in a single table.CThe primary key constraint can be referred by only one foreign key constraint.DThe primary key constraint can be imposed by combining more than one column.EThe non-deferrable primary key constraint creates an unique index on the primary key column if it is not already indexed.
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?（）AALTER TABLE students ADD PRIMARY KEY student_id;BALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student _ id);CALTER TABLE students ADD CONSTRAINT stud _ id _pk PRIMARY KEY (student _ id);DALTER TABLE students MODIFY CONSTRAINT stud _ id _pk PRIMARY KEY (student _ id);
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?（）AALTER TABLE students ADD PRIMARY KEY student_id;BALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);CALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;DALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);EALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
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.
单选题Which statement adds a constraint that ensures the CUSTOMER_NAME column of the CUSTOMERS table holds a value?（）AALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;BALTER TABLE customers MODIFY CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;CALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn NOT NULL;DALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn IS NOT NULL;EALTER TABLE customers MODIFY name CONSTRAINT cust_name_nn NOT NULL;FALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name NOT NULL;