Oracle 1z0-883 問題集

質問 1：
The 'allplicationdb' is using innoDB and consuming a large amount of file system space. You have a /backup partition available on NFS where backups are stored.
You investigate and gather the following information:
[mysqld] Datadir=/var/lib/mysql/ Innodb_file_per_table=0
Three tables are stored in the innoDB shared tablespace and the details are as follows: -The table data_current has 1,000,000 rows.
-The table data_reports has 1,500,000 rows. -The table data_archive has 4,500,000 rows. Shell> is -1 /var/lib/mysql/ -rw-rw---- 1 mysql mysql 744G Aug 26 14:34 ibdata1 -rw-rw---- 1 mysql mysql 480M Aug 26 14:34 ib_logfile0 -rw-rw---- 1 mysql mysql 480M Aug 26 14:34 ib_logfile1 ...
You attempt to free space from ibdata1 by taking a mysqldump of the data_archive table and storting it on your backup partition.
Shell> mysqldump - u root - p applicationdb data_archive > /backup/data_archive.sql
Mysql> DROP TABLE data_archive;
Which set of actions will allow you to free disk space back to the file system?
A. Execute OPTIMIZE TABLE so that the InnoDB engine frees unused pages on disk back to the
file system:
Mysql> OPTIMIZE TABLE data_current, data_reports;
B. Take a backup, stop the server, remove the data files, and restore the backup:
Shell> mysqldump - u root -p applicationdb / > /backup/applicationdb.sql
Shell> /etc/init.d/mysql stop
Shell> cd /var/lib/mysql/
Shell> rm ibdata1 ib_logfile0 ib_logfile1
Shell> /etc/init.d/mysql start
Shell> mysql - u root - p applicationdb < /backup/applicationdb.sql
C. Set the server to use its own tablespace, and then alter the table so that data is moved from the
shared tablespace to its own:
Mysql> SET GLOBAL innodb_file_per_table=1;
Mysql> ALTER TABLE data_current ENGINE=InnoDB;
Mysql> ALTER TABLE data_repors ENGINE=InnoDB;
D. Enable compression on the table, causing InnoDB to release unused pages on disk to the file
system:
Mysql> SET GLOBLE innodb_file_per_table=1;
Mysql> SET GLOBLE innodb_file_format=Barramcuda;
Mysql> ALTER TABLE data_current ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=8;
Mysql> ALTER TABLE data_history ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=8;
正解：B

質問 2：
You are investigating the performance of the server and see the following information:
-Events_waits_summary_global_by_event_name in the performance schema shows that the wait/synch/mutex/sql/LOCK_table_cache event is dominating other wait events.
-The table_open_cache_overflows status variable is 0.
Which action should be taken to remove the performance bottleneck described here?
A. Increase the value of table_open_cache.
B. Increase the value of table_definition_cache.
C. Decrease the value of table_open_cache.
D. Decrease the value of table_definition_cache.
E. Decrease the value of table_open_cache_instances.
F. Increase the value of table_open_cache_instances.
正解：A
解説: (Topexam メンバーにのみ表示されます)

質問 3：
Assume that you want to know which Mysql Server options were set to custom values.
Which two methods would you use to find out?
A. Check the output of SHOW GLOBAL VARIABLES and compare it with default values.
B. Check the configuration files in the order in which they are read by the Mysql Server and compare them with default values.
C. Check the command-line options provided for the Mysql Server and compare them with default values.
D. Query the INFORMATION_SCHEMA.GLOBAL_VARIABLES table and compare the result with default values.
正解：A,D

質問 4：
What are three methods to reduce Mysql server exposure to remote connections?
A. Setting specific GRANT privilege to limit remote authentication
B. Using the sql_mode=STRICT_SECURE after connections are established for encrypted communications
C. Using SSL when transporting data over remote networks
D. Setting - mysql_secure_configuration to enable paranoid mode
E. Setting -- skip-networking when remote connections are not required
正解：A,B,E

質問 5：
Which High Availability solution can provide a consistent, time-delayed (for example, one hour) snapshot of the live production database?
A. MySQL Replication
B. Distributed Replication Block Device
C. Windows Server Failover Clustering
D. MySQL Cluster
正解：A