单选题You own a table called EMPLOYEES with this table structure: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE What happens when you execute this DELETE statement? DELETE employees; （）A You get an error because

题目
单选题
You own a table called EMPLOYEES with this table structure: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE What happens when you execute this DELETE statement? DELETE employees; （）
A

You get an error because of a primary key violation.

B

The data and structure of the EMPLOYEES table are deleted.

C

The data in the EMPLOYEES table is deleted but not the structure.

D

You get an error because the statement is not syntactically correct.

相似考题

1.Examine the statement: Create synonym emp for hr. employees; What happens when you issue the statement? ()A. An error is generated.B. You will have two identical tables in the HR schema with different names.C. You create a table called employees in the HR schema based on you EMP table.D. You create an alternative name for the employees table in the HR schema in your own schema.

2.Evaluate the SQL statement DROP TABLE DEPT: Which four statements are true of the SQL statement? ()A. You cannot roll back this statement.B. All pending transactions are committed.C. All views based on the DEPT table are deleted.D. All indexes based on the DEPT table are dropped.E. All data in the table is deleted, and the table structure is also deleted.F. All data in the table is deleted, but the structure of the table is retained.G. All synonyms based on the DEPT table are deleted.

3.You added a PHONE_NUMBER column of NUMBER data type to an existing EMPLOYEES table. The EMPLOYEES table already contains records of 100 employees. Now, you want to enter the phone numbers of each of the 100 employees into the table. Some of the employees may not have a phone number available. Which data manipulation operation do you perform? （）A. MERGEB. INSERTC. UPDATED. ADDE. ENTERF. You cannot enter the phone numbers for the existing employee records.

4.You own a table called EMPLOYEES with this table structure: EMPLOYEE_ID NUMBER Primary KeyFIRST_NAME VARCHAR2(25)LAST_NAME VARCHAR2(25)HIRE_DATE DATEWhat happens when you execute this DELETE statement? DELETE employees; （）A. You get an error because of a primary key violation.B. The data and structure of the EMPLOYEES table are deleted.C. The data in the EMPLOYEES table is deleted but not the structure.D. You get an error because the statement is not syntactically correct.

参考答案和解析
正确答案： B
解析： 暂无解析
更多“You own a table called EMPLOYEES with this table structure:”相关问题

  • 第1题：

    Examine the structure of the EMPLOYEES table:You need to update the records of employees 103 and 115. The UPDATE statement you specify should update the rows with the values specified below:Which UPDATE statement meets the requirements?（）

    A.

    B.

    C.

    D.

    E.


    参考答案：C

  • 第2题：

    Examine the structure of the EMPLOYEES table:You issue these statements:At the end of this transaction, what is true?()

    A. You have no rows in the table.

    B. You have an employee with the name of James.

    C. You cannot roll back to the same savepoint more than once.

    D. Your last update fails to update any rows because employee ID 180 was already eleted.


    参考答案：A

  • 第3题：

    Examine the data in the EMPLOYEES table.On the EMPLOYEES table, EMPLOYEE_ID is the primary key. MGR_ID is the ID of managers and refers to the EMPLOYEE_ID. The JOB_ID column is a NOT NULL column.Evaluate this DELETE statement:Why does the DELETE statement fail when you execute it?（）

    A. There is no row with dept_id 90 in the EMPLOYEES table.

    B. You cannot delete the JOB_ID column because it is a NOT NULL column.

    C. You cannot specify column names in the DELETE clause of the DELETE statement.

    D. You cannot delete the EMPLOYEE_ID column because it is the primary key of the table.


    参考答案：C

  • 第4题：

    You added a PHONE_NUMBER column of NUMBER data type to an existing EMPLOYEES table. The EMPLOYEES table already contains records of 100 employees. Now, you want to enter the phone numbers of each of the 100 employees into the table. Some of the employees may not have a phone number available. Which data manipulation operation do you perform?（）

    • A、MERGE
    • B、INSERT
    • C、UPDATE
    • D、ADD
    • E、ENTER
    • F、You cannot enter the phone numbers for the existing employee records.

    正确答案:C

  • 第5题：

    You issued the following command to drop the PRODUCTS table: SQL> DROP TABLE products; What is the implication of this command?（）

    • A、All data along with the table structure is deleted 
    • B、The pending transaction in the session is committed 
    • C、All indexes on the table will remain but they are invalidated 
    • D、All views and synonyms will remain but they are invalidated 
    • E、All data in the table are deleted but the table structure will remain

    正确答案:A,B,D

  • 第6题：

    Evaluate the SQL statement DROP TABLE DEPT: Which four statements are true of the SQL statement? （）

    • A、You cannot roll back this statement.
    • B、All pending transactions are committed.
    • C、All views based on the DEPT table are deleted.
    • D、All indexes based on the DEPT table are dropped.
    • E、All data in the table is deleted, and the table structure is also deleted.
    • F、All data in the table is deleted, but the structure of the table is retained.
    • G、All synonyms based on the DEPT table are deleted.

    正确答案:A,B,D,E

  • 第7题：

    Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_NAME VARCHAR2(30) JOB_ID NUMBER SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You created a sequence called EMP_ID_SEQ in order to populate sequential values for the EMPLOYEE_ID column of the EMPLOYEES table. Which two statements regarding the EMP_ID_SEQ sequence are true? （）

    • A、You cannot use the EMP_ID_SEQ sequence to populate the JOB_ID column.
    • B、The EMP_ID_SEQ sequence is invalidated when you modify the EMPLOYEE_ID column.
    • C、The EMP_ID_SEQ sequence is not affected by modifications to the EMPLOYEES table.
    • D、Any other column of NUMBER data type in your schema can use the EMP_ID_SEQ sequence.
    • E、The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEES table.
    • F、The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEE_ID column.

    正确答案:C,D

  • 第8题：

    单选题
    Examine the statement:Create synonym emp for hr. employees;What happens when you issue the statement?（）
    A

    An error is generated.

    B

    You will have two identical tables in the HR schema with different names.

    C

    You create a table called employees in the HR schema based on you EMP table.

    D

    You create an alternative name for the employees table in the HR schema in your own schema.


    正确答案： A
    解析： 暂无解析

  • 第9题：

    单选题
    You executed the following SQL statement to shrink the EMPLOYEES table segment stored in the EXAMPLE tablespace: ALTER TABLE employees SHRINK SPACE CASCADE; Which statement is correct in this scenario?（）
    A

    The EMPLOYEES table will be changed to read-only mode during the shrink operation.

    B

    The indexes created on the EMPLOYEES table will need to be rebuilt after the shrink operation is over.

    C

    The shrink behavior will be cascaded to all dependent segments of the table that support a shrink operation.

    D

    Data manipulation language (DML) operations will not be possible on the EMPLOYEES table during the COMPACTION phase of the shrink operation.


    正确答案： A
    解析： 暂无解析

  • 第10题：

    单选题
    The EMPLOYEES table is stored in the SAMPLE tablespace.  The corresponding IPK_EMP index for the EMPLOYEES table’s primary key is stored in the INDX tablespace.  Out of 12 partitions， only partition P1 of the SALES table is stored in the SAMPLE tablespace.  Which object will be exported by this command？（）   exp system/manager tablespaces=SAMPLE
    A

    Only the EMPLOYEES table.

    B

    Only the EMPLOYEES table and its corresponding primary key index.

    C

    The EMPLOYEES table and partition P1.

    D

    The EMPLOYEES table， IPK_EMP index， and the SALES table.


    正确答案： B
    解析： 暂无解析

  • 第11题：

    多选题
    Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_NAME VARCHAR2(30) JOB_ID NUMBER/ SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You created a sequence called EMP_ID_SEQ in orderto populate sequential values for the EMPLOYEE_ID column of the EMPLOYEES table. Which two statements regarding the EMP_ID_SEQ sequence are true? （）
    A

    You cannot use the EMP_ID_SEQ sequence to populate the JOB_ID column.

    B

    The EMP_ID_SEQ sequence is invalidated when you modify the EMPLOYEE_ID column.

    C

    The EMP_ID_SEQ sequence is not affected by modifications to the EMPLOYEES table.

    D

    Any other column of NUMBER data type in your schema can use the EMP_ID_SEQ sequence.

    E

    The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEES table.

    F

    The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEE_ID column.


    正确答案： F,A
    解析： 暂无解析

  • 第12题：

    多选题
    Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_NAME VARCHAR2(30) JOB_ID NUMBER SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You created a sequence called EMP_ID_SEQ in order to populate sequential values for the EMPLOYEE_ID column of the EMPLOYEES table. Which two statements regarding the EMP_ID_SEQ sequence are true? （）
    A

    You cannot use the EMP_ID_SEQ sequence to populate the JOB_ID column.

    B

    The EMP_ID_SEQ sequence is invalidated when you modify the EMPLOYEE_ID column.

    C

    The EMP_ID_SEQ sequence is not affected by modifications to the EMPLOYEES table.

    D

    Any other column of NUMBER data type in your schema can use the EMP_ID_SEQ sequence.

    E

    The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEES table.

    F

    The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEE_ID column.


    正确答案： B,E
    解析： 暂无解析

  • 第13题：

    Examine the structure of the EMPLOYEES table:What is the correct syntax for an inline view?()

    A.

    B.

    C.

    D.


    参考答案：A

  • 第14题：

    Examine the data from the EMP table:The COMMISSION column shows the monthly commission earned by the employee.Which three tasks would require subqueries or joins in order to perform in a single step?（）

    A. Deleting the records of employees who do not earn commission.

    B. Increasing the commission of employee 3 by the average commission earned in department 20.

    C. Finding the number of employees who do NOT earn commission and are working for department 20.

    D. Inserting into the table a new employee 10 who works for department 20 and earns a commission that is equal to the commission earned by employee 3.

    E. Creating a table called COMMISSION that has the same structure and data as the columns EMP_ID and COMMISSIONS of the EMP table.

    F. Decreasing the commission by 150 for the employees who are working in department 30 and earning a commission of more then 800.


    参考答案：B, D, F

  • 第15题：

    Examine the data in the EMPLOYEES and DEPARTMENTS tables:Also examine the SQL statements that create the EMPLOYEES and DEPARTMENTS tables:On the EMPLOYEES table, EMPLOYEE_ID is the primary key.MGR_ID is the ID of managers and refers to the EMPLOYEE_ID.DEPT_ID is foreign key to DEPARTMENT_ID column of the DEPARTMENTS table.On the DEPARTMENTS table, DEPARTMENT_ID is the primary key.Examine this DELETE statement:What happens when you execute the DELETE statement?（）

    A. Only the row with department ID 40 is deleted in the DEPARTMENTS table.

    B. The statement fails because there are child records in the EMPLOYEES table with department ID 40.

    C. The row with department ID 40 is deleted in the DEPARTMENTS table. Also the rows with employee IDs 110 and 106 are deleted from the EMPLOYEES table.

    D. The row with department ID 40 is deleted in the DEPARTMENTS table. Also the rows with employee IDs 106 and 110 and the employees working under employee 110 are deleted from the EMPLOYEES table.

    E. The row with department ID 40 is deleted in the DEPARTMENTS table. Also all the rows in the EMPLOYEES table are deleted.

    F. The statement fails because there are no columns specifies in the DELETE clause of the DELETE statement.


    参考答案：B

  • 第16题：

    The database administrator of your company created a public synonym called HR for the HUMAN_RESOURCES table of the GENERAL schema, because many users frequently use this table. As a user of the database, you created a table called HR in your schema. What happens when you execute this query? SELECT * FROM HR; （）

    • A、You obtain the results retrieved from the public synonym HR created by the database administrator.
    • B、You obtain the results retrieved from the HR table that belongs to your schema.
    • C、You get an error message because you cannot retrieve from a table that has the same name as a public synonym.
    • D、You obtain the results retrieved from both the public synonym HR and the HR table that belongs to your schema, as a Cartesian product.
    • E、You obtain the results retrieved from both the public synonym HR and the HR table that belongs to your schema, as a FULL JOIN.

    正确答案:B

  • 第17题：

    The EMPLOYEES table is stored in the USERS tablespace. You need to check if the EMPLOYEES table is affected by the block corruption found in the USERS tablespace. Which option would you use？（） 

    • A、the DBNEWID utility
    • B、the ANALYZE command
    • C、the RMAN LIST command
    • D、the RMAN REPORT command
    • E、the RMAN CROSSCHECK command
    • F、the RMAN BLOCKRECOVER command

    正确答案:B

  • 第18题：

    Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_NAME VARCHAR2(30) JOB_ID NUMBER/ SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You created a sequence called EMP_ID_SEQ in orderto populate sequential values for the EMPLOYEE_ID column of the EMPLOYEES table. Which two statements regarding the EMP_ID_SEQ sequence are true? （）

    • A、You cannot use the EMP_ID_SEQ sequence to populate the JOB_ID column.
    • B、The EMP_ID_SEQ sequence is invalidated when you modify the EMPLOYEE_ID column.
    • C、The EMP_ID_SEQ sequence is not affected by modifications to the EMPLOYEES table.
    • D、Any other column of NUMBER data type in your schema can use the EMP_ID_SEQ sequence.
    • E、The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEES table.
    • F、The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEE_ID column.

    正确答案:C,D

  • 第19题：

    You have just performed a FLASHBACK TABLE operation using the following command：   flashback table employees to scn 123456；   The employees table has triggers associated with it.  Which of the following statements is true regarding the state of the triggers during the Flashback Table operation？（）  

    • A、 All the triggers are disabled.
    • B、 All the triggers are enabled by default.
    • C、 Enabled triggers remain enabled and disabled triggers remain disabled.
    • D、 Triggers are deleted when a Flashback Table operation is performed.

    正确答案:A

  • 第20题：

    单选题
    You own a table called EMPLOYEES with this table structure: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE What happens when you execute this DELETE statement? DELETE employees; （）
    A

    You get an error because of a primary key violation.

    B

    The data and structure of the EMPLOYEES table are deleted.

    C

    The data in the EMPLOYEES table is deleted but not the structure.

    D

    You get an error because the statement is not syntactically correct.


    正确答案： C
    解析： 暂无解析

  • 第21题：

    多选题
    You issued the following command to drop the PRODUCTS table: SQL> DROP TABLE products; What is the implication of this command?（）
    A

    All data along with the table structure is deleted

    B

    The pending transaction in the session is committed

    C

    All indexes on the table will remain but they are invalidated

    D

    All views and synonyms will remain but they are invalidated

    E

    All data in the table are deleted but the table structure will remain


    正确答案： B,C
    解析： 暂无解析

  • 第22题：

    单选题
    You added a PHONE_NUMBER column of NUMBER data type to an existing EMPLOYEES table. The EMPLOYEES table already contains records of 100 employees. Now, you want to enter the phone numbers of each of the 100 employees into the table. Some of the employees may not have a phone number available. Which data manipulation operation do you perform?（）
    A

    MERGE

    B

    INSERT

    C

    UPDATE

    D

    ADD

    E

    ENTER

    F

    You cannot enter the phone numbers for the existing employee records.


    正确答案： D
    解析： 暂无解析

  • 第23题：

    单选题
    You executed the following SQL statement to shrink the EMPLOYEES table segment stored in the EXAMPLE tablespace: ALTER TABLE employees SHRINK SPACE CASCADE; Which statement is correct in this scenario?（）
    A

    The data in the segment will be compacted but the high water mark will not be adjusted 

    B

    The EMPLOYEES table will be changed to read-only mode during the shrink operation 

    C

    The indexes created on the EMPLOYEES table will need to be rebuilt after the shrink operation is over

    D

    The shrink behavior will be cascaded to all dependent segments of the table that support a shrink operation 

    E

    Data manipulation language (DML) operations will not be possible on the EMPLOYEES table during the COMPACTION phase of the shrink operation


    正确答案： C
    解析： 暂无解析

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