Oracle 1z0-882 問題集

質問 1：
The people table contains the data as shown:

Which two statements return two rows each?
A. SELECT DISTINCT last_name, first_name FROM people
B. SELECT 1, 2 FROM people WHERE last _name ='smith'
C. SELECT first_name, last _name FROM people WHERE age LIKE '2'
D. SELECT first _name, last_name FROM people LIMIT 1, 2
E. SELECT 1,2 FROM people GROUP BY last_name
正解：D,E

質問 2：
Which three connector/J connection strings can be used to connect to the MYSQL server?
A. Jdbc :mysqli://localhost/test?user=xxx&password=xxx
B. Jdbc:mysql:proxy://localhost/test?user=xxx&password=xxx
C. Jdbc :mysql:loadbalance://master.slave1,slave2/test?user=xxx&password=xxx
D. Jdbc:mysq1://localhost/test?user =xxx&password=xxx
E. Jdbc :mysql:replication://master,slave1.slave2. /test?user=xxx&password=xxx
正解：C,D,E

質問 3：
Given the table City:
SELECT Name
FROM City
WHERE CountryCode = 'USA" OR WHERE CountryCode= 'JPN'
What does this statement procedure?
A. No result set is returned and an error message is given.
B. Two result sets each containing a single column with the names of cities from country codes USA and JPN.
C. A single result set with two columns containing the names from country codes USA and JPN.
D. A single result set with one column that contains the names of cities from country codes USA and JPN.
正解：A

質問 4：
Which statement is true about the difference between HASH and BTREE INDEXES?
A. HASH indexes support rightmost prefixing of keys, which makes them faster than BTREE indexes in many causes.
B. HASH indexes are used only for equality comparisons (= or<=>),whereas BTREE indexes can also be used for range
searches (>or<).
C. HASH indexes are much faster than BTREE indexes but can only be used for a single column.
D. HASH indexes can be used by the optimizer to speed up ORDER BY operations and not BTREE indexes.
正解：B
解説: (Topexam メンバーにのみ表示されます)

質問 5：
You attempt to create two new tables:
CREATE TABLE 'warehouse' (
'id' int (11) NOT NULL AUTO_INCREMENT,
'name' varchar (20) NOT NULL,
'phone' varchar (20) NOT NULL,
PRIMARY KEY (' id)
) ENGINE=MyISAM
CREATE TABLE 'warehouseitem' (
'warehouse_id' bigint (11) NOT NULL,
'item_id' int (11) NOT NULL,
'count' int(11) NOT NULL DEFAULT '0',
KEY "warehouse_id' ('warehouse-id) ,
FOREIGN KEY (warehouse_id) REFFERENCES warehouse (id)
) ENGINE= InnoDB
You get this error :
ERROR 1215 ( HYooo): cannot add foreign key constraint
Which two changes are required to permit these statements to execute without any error?
A. A UNIQUE key must be defined for the columns ('item_id','warehouse_id').
B. The data types of the 'warehouse'.'id' and ' warehouseitem.warehouse_is columns must match.
C. The foreign key clause must be reversed: FOREIGN KEY warehouse(1)REFERENCES (warehouse-id).
D. The 'warehouseitem' table must be managed by the MySAm storage engine.
E. The warehouse_id' column must be renamed 'id' to match the definition on the 'warehouse' table.
F. The 'warehouse-table must be managed by the InnoDB storage engine.
正解：B,F