多項選擇題

The CUSTOMERS table has these columns:

The CUSTOMER_ID column is the primary key for the table.Which two statements find the number of customers? （）

A. SELECT TOTAL(*)   FROM customers;
B. SELECT COUNT(*)   FROM customers;
C. SELECT TOTAL(customer_id)   FROM customers;
D. SELECT COUNT(customer_id)   FROM customers;
E. SELECT COUNT(customers)   FROM customers;
F. SELECT TOTAL(customer_name)   FROM customers;

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單項選擇題

Examine the description of the EMPLOYEES table:
EMP_ID NUMBER(4) NOT NULL
LAST_NAME VARCHAR2(30) NOT NULL
FIRST_NAME VARCHAR2(30)
DEPT_ID NUMBER(2)
Which statement produces the number of different departments that have employees with last name Smith?（）

A. SELECT COUNT (*) FROM employees WHERE last _name='smith';
B. SELECT COUNT (dept_id) FROM employees WHERE last _name='smith';
C. SELECT DISTINCT (COUNT (dept_id) FROM employees WHERE last _name='smith';
D. SELECT COUNT (DISTINCT dept_id) FROM employees WHERE last _name='smith';
E. SELECT UNIQE (dept_id) FROM employees WHERE last _name='smith';

單項選擇題

Which is an iSQL*Plus command?（）

A. INSERT
B. UPDATE
C. SELECT
D. DESCRIBE
E. DELETE
F. RENAME

The CUSTOMERS table has these columns: The CUSTOMER_ID column is the primary key for the table.Which two statements find the number of customers? （）

你可能感興趣的試題

Examine the description of the EMPLOYEES table: EMP_ID NUMBER(4) NOT NULL LAST_NAME VARCHAR2(30) NOT NULL FIRST_NAME VARCHAR2(30) DEPT_ID NUMBER(2) Which statement produces the number of different departments that have employees with last name Smith?（）

Which is an iSQL*Plus command?（）

The CUSTOMERS table has these columns:

The CUSTOMER_ID column is the primary key for the table.Which two statements find the number of customers? （）

Examine the description of the EMPLOYEES table:
EMP_ID NUMBER(4) NOT NULL
LAST_NAME VARCHAR2(30) NOT NULL
FIRST_NAME VARCHAR2(30)
DEPT_ID NUMBER(2)
Which statement produces the number of different departments that have employees with last name Smith?（）