SELECT TOTAL(*) FROM customer;
SELECT COUNT(*) FROM customer;
SELECT TOTAL(customer_id) FROM customer;
SELECT COUNT(customer_id) FROM customer;
SELECT COUNT(customers) FROM customer;
SELECT TOTAL(customer_name) FROM customer;
第1题：
The CUSTOMERS table has these columns:CUSTOMER_ID NUMBER(4) NOT NULLCUSTOMER_NAME VARCHAR2(100) NOT NULLSTREET_ADDRESS VARCHAR2(150)CITY_ADDRESS VARCHAR2(50)STATE_ADDRESS VARCHAR2(50)PROVINCE_ADDRESS VARCHAR2(50)COUNTRY_ADDRESS VARCHAR2(50)POSTAL_CODE VARCHAR2(12)CUSTOMER_PHONE VARCHAR2(20)The CUSTOMER_ID column is the primary key for the table.You need to determine how dispersed your customer base is. Which expression finds the number of different countries represented in the CUSTOMERS table?（）
A.COUNT(UPPER(country_address))
B.COUNT(DIFF(UPPER(country_address)))
C.COUNT(UNIQUE(UPPER(country_address)))
D.COUNT DISTINCT UPPER(country_address)
E.COUNT(DISTINCT (UPPER(country_address)))
第2题：
“雇员”表包含以下列：姓氏VARCHAR2（25） 名字VARCHAR2（25） 电子邮件VARCHAR2（50）如果要编写以下SELECT语句来检索具有电子邮件地址的雇员的姓名。SELECT姓氏||’，’||名字"雇员姓名"FROM雇员；则应使用哪条WHERE子句来完成此条语句？（）
第3题：
The CUSTOMERS table has these columns:CUSTOMER_ID NUMBER (4) NOT NULLCUSTOMER_NAME VARCHAR2 (100) NOT NULLSTREET_ADDRESS VARCHAR2 (150)CITY_ADDRESS VARHCAR2 (50)STATE_ADDRESS VARCHAR2 (50)PROVINCE_ADDRESS VARCHAR2 (50)COUNTRY_ADDRESS VARCHAR2 (50)POSTAL_CODE VARCHAR2 (12)CUSTOMER_PHONE VARCHAR2 (20)The CUSTOMER_ID column is the primary key for the table.You need to determine how dispersed your customer base is.Which expression finds the number of different countries represented in the CUSTOMERS table?（）
A. COUNT(UPPER(country_address))
B. COUNT(DIFF(UPPER(country_address)))
C. COUNT(UNIQUE(UPPER(country_address)))
D. COUNT DISTINTC UPPER(country_address)
E. COUNT(DISTINTC (UPPER(country_address)))
第4题：
修改表Department添加列Leader数据类型varchar2（10）的语句是：Alter table Department add Leader varchar2（10）；
第5题：
You executed the following code： SQL> CREATE TABLE COUNTRY （COUNTRY_ID CHAR（2） CONSTRAINT COUNTRY_ID_nn NOT NULL， COUNTRY_NAME VARCHAR2（20）， CURRENCY_NAME VARCHAR2（20）， CONSTRAINT COUNTRY_ID_PK PRIMARY KEY （COUNTRY_ID）） ORGANIZATION INDEX； In which tablespace will the mapping table be created？（）
第6题：
（若oracle数据库不了解，可以用sql）
test1
ID Varchar2(6) 主键
NAME Varchar2(15)
Test2
Use_ID Varchar2(6) 主键关联TEST1的主键的ID
PASSword Varchar2(10)
第7题：
“雇员”表包含以下列：姓氏VARCHAR2（25） 名字VARCHAR2（25） 电子邮件VARCHAR2（50）如果要编写以下SELECT语句来检索具有电子邮件地址的雇员的姓名。SELECT姓氏||’，’||名字"雇员姓名"FROM雇员；则应使用哪条WHERE子句来完成此条语句？（）
第8题：
You need to produce a report for mailing labels for all customers. The mailing label must have only the customer name and address. The CUSTOMERS table has these columns:CUST_ID NUMBER(4) NOT NULLCUST_NAME VARCHAR2(100) NOT NULLCUST_ADDRESS VARCHAR2(150)CUST_PHONE VARCHAR2(20)Which SELECT statement accomplishes this task?（）
A. SELECT* FROM customers;
B. SELECT name, address FROM customers;
C. SELECT id, name, address, phone FROM customers;
D. SELECT cust_name, cust_address FROM customers;
E. SELECT cust_id, cust_name, cust_address, cust_phone FROM customers;
第9题：
请观察PRODUCT表和SUPPLIER表的结构: PRODUCT PRODUCT_ID NUMBER NOT NULL, Primary Key PRODUCT_NAME VARCHAR2 (25) SUPPLIER_ID NUMBER （ SUPPLIER表的SUPPLIER_ID的外键） LIST_PRICE NUMBER (7,2) COST NUMBER (7,2) QTY_IN_STOCK NUMBER QTY_ON_ORDER NUMBER REORDER_LEVEL NUMBER REORDER_QTY NUMBER SUPPLIER SUPPLIER_ID NUMBER NOT NULL, Primary Key SUPPLIER_NAME VARCHAR2 (25) ADDRESS VARCHAR2 (30) CITY VARCHAR2 (25) REGION VARCHAR2 (10) POSTAL_CODE VARCHAR2 (11) 请评估以下语句： ALTER TABLE suppliers DISABLE CONSTRAINT supplier_id_pk CASCADE; 该语句用于执行什么任务（）
第10题：
The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) The CUSTOMER_ID column is the primary key for the table. Which two statements find the number of customers? （）