单项选择题
Examine the structure of the EMPLOYEES and NEW_EMPLOYEES tables:
EMPLOYEES
EMPLOYEE_ID NUMBER Primary Key
FIRST_NAME VARCHAR2(25)
LAST_NAME VARCHAR2(25)
HIRE_DATE DATE
NEW_EMPLOYEES
EMPLOYEE_ID NUMBER Primary Key
NAME VARCHAR2(60)
Which UPDATE statement is valid?()
A.UPDATEnew_employeesSETname=(SELECTlast_nameFirst_nameFROMemployeesWHEREemployee_id=180)WHEREemployee_id=180;
B.UPDATEnew_employeesSETname=(SELECTlast_nameFirst_nameFROMemployees)WHEREemployee_id=180;
C.UPDATEnew_employeesSETname=(SELECTlast_nameFirst_nameFROMemployeesWHEREemployee_id=180) WHEREemployee_id=(SELECTemployee_idFROMnew_employees);
D.UPDATEnew_employeesSETname=(SELECTlast_nameFirst_nameFROMemployeesWHEREemployee_id=(SELECTemployee_idFROMnew_employees) WHEREemployee_id=180;
相关考题
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单项选择题
Which view should a user query to display the columns associated with the constraints on a table owned by the user?()
A.USER_CONSTRAINTS
B.USER_OBJECTS
C.ALL_CONSTRAINTS
D.USER_CONS_COLUMNS
E.USER_COLUMNS -
多项选择题
Which four are attributes of single row functions? ()
A.cannot be nested
B.manipulate data items
C.act on each row returned
D.return one result per row
E.accept only one argument and return only one value
F.accept arguments which can be a column or an expression -
单项选择题
Evaluate this SQL statement: e.employee_id, (.15* e.salary) + (.5 * e.commission_pct) + (s.sales_amount * (.35 * e.bonus)) AS CALC_VALUE FROM employees e, sales s WHERE e.employee_id = s.emp_id; What will happen if you remove all the parentheses from the calculation?()
A.The value displayed in the CALC_VALUE column will be lower.
B.The value displayed in the CALC_VALUE column will be higher.
C.There will be no difference in the value displayed in the CALC_VALUE column.
D.An error will be reported.
