SELECT city_address, COUNT(*) FROM customers WHERE city _ address IN ('Los Angeles','San Fransisco');
SELECT city_address, COUNT (*) FROM customers WHERE city address IN ( 'Los Angeles', 'San Fransisco') GROUP BY city_address;
SELECT city_address, COUNT(customer_id) FROM customers WHERE city_address IN ( 'Los Angeles', 'San Fransisco') GROUP BY city_address, customer_ id;
SELECT city_address, COUNT (customer_id) FROM customers GROUP BY city_ address IN ('Los Angeles','San Fransisco');
第1题:
A. Statistics collection is not done for the CUSTOMERS table when schema stats are gathered.
B. Statistics collection is not done for the CUSTOMERS table when database stats are gathered.
C. Any existing statistics for the CUSTOMERS table are still available to the optimizer at parse time.
D. Statistics gathered on the CUSTOMERS table when schema stats are gathered are stored as pending statistics.
E. Statistics gathered on the CUSTOMERS table when database stats are gathered are stored as pending statistics.
第2题:
3,2,1,4
2,3,4,1
4,1,3,2
3,2,4,1
第3题:
Automatic statistics collection is stopped for the CUSTOMERS table.
Statistics for the CUSTOMERS table are locked and cannot be overwritten.
Existing statistics for the CUSTOMERS table become unusable for the query optimizer.
Subsequently, statistics gathered on the CUSTOMERS table are stored as pending statistics
第4题:
Statistics collection is not done for the CUSTOMERS table when schema stats are gathered.
Statistics collection is not done for the CUSTOMERS table when database stats are gathered.
Any existing statistics for the CUSTOMERS table are still available to the optimizer at parse time.
Statistics gathered on the CUSTOMERS table when schema stats are gathered are stored as pending statistics.
Statistics gathered on the CUSTOMERS table when database stats are gathered are stored as pending statistics.
第5题:
Automatic statistics collection is stopped for the CUSTOMERS table.
Statistics for the CUSTOMERS table are locked and cannot be overwritten.
Existing statistics for the CUSTOMERS table become unusable for the query optimizer.
Subsequently, statistics gathered on the CUSTOMERS table are stored as pending statistics.
第6题:
SELECT customer_id, customer_name FROM customers WHERE postal_code CONTAINS NULL;
SELECT customer_id, customer_name FROM customers WHER postal_code = ' ___________';
SELECT customer_id, customer_name FROM customers WHERE postal _ code IS NULL;
SELECT customer_id, customer_name FROM customers WHERE postal code IS NVL;
SELECT customer_id, customer_name FROM customers WHERE postal_code = NULL;
第7题:
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8题:
COUNT(UPPER(country_address))
COUNT(DIFF(UPPER(country_address)))
COUNT(UNIQUE(UPPER(country_address)))
COUNT DISTINCT UPPER(country_address)
COUNT(DISTINCT (UPPER(country_address)))
第9题:
You need to change the definition of an existing table. The COMMERCIALS table needs its DESCRIPTION column changed to hold varying length characters up to 1000 bytes. The column can currently hold 500 bytes per value. The table contains 20000 rows. Which statement is valid?()
第10题:
CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE = SYSDATE);
CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE DEFAULT SYSDATE);
CREATE OR REPLACE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE DEFAULT SYSDATE);
CREATE OR REPLACE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status NUMBER (10), date_ordered DATE = SYSDATE);
CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status NUMBER (10), date_ordered DATE = SYSDATE);
CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status NUMBER (10), date_ordered DATE DEFAULT SYSDATE);
第11题:
ALTER TABLE commercials MODIFY (description CHAR2(2000));
ALTER TABLE commercials CHANGE (description CHAR2(2000));
ALTER TABLE commercials CHANGE (description VARCHAR2 (2000));
ALTER TABLE commercials MODIFY (description VARCHAR2 (2000));
You cannot increase the size of a column if the table has rows.
第12题:
Only the ORD_CUSTOMER_IX1 index created.
Both the indexes are updated when a row is inserted, updated, or deleted in the ORDERS table.
Both the indexes are created: however, only ORD_CUSTOMERS_IX1 is used by the optimizer for queries on the ORDERS table.
The ORD_CUSTOMER_IX1 index is not used by the optimizer even when the OPTIMIZER_USE_INVISIBLE_INDEXES parameters is set to true.
Both the indexes are created and used by the optimizer for queries on the ORDERS table.
Both the indexes are created: however, only ORD_CUSTOMERS_IX2 is used by the optimizer for queries on the ORDERS table.
第13题:
SELECT city_address, COUNT(*) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco');
SELECT city_address, COUNT(*) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco') GROUP BY city_address;
SELECT city_address, COUNT(customer_id) FROM customers WHERE city_address IN ('Los Angeles', 'San Francisco') GROUP BY city_address, customer_id;
SELECT city_address, COUNT(customer_id) FROM customers GROUP BY city_address IN ('Los Angeles', 'San Francisco');
第14题:
ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;
ALTER TABLE customers MODIFY CONSTRAINT cust_name_nn CHECK customer_name IS NOT NULL;
ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn NOT NULL;
ALTER TABLE customers MODIFY customer_name CONSTRAINT cust_name_nn IS NOT NULL;
ALTER TABLE customers MODIFY name CONSTRAINT cust_name_nn NOT NULL;
ALTER TABLE customers ADD CONSTRAINT cust_name_nn CHECK customer_name NOT NULL;
第15题:
SELECT city_address, COUNT(*) FROM customers WHERE city _ address IN ('Los Angeles','San Fransisco');
SELECT city_address, COUNT (*) FROM customers WHERE city address IN ( 'Los Angeles', 'San Fransisco') GROUP BY city_address;
SELECT city_address, COUNT(customer_id) FROM customers WHERE city_address IN ( 'Los Angeles', 'San Fransisco') GROUP BY city_address, customer_ id;
SELECT city_address, COUNT (customer_id) FROM customers GROUP BY city_ address IN ('Los Angeles','San Fransisco');