oracle 1z0-908 practice test

Question 1

Which two storage engines provide a view of the data consistent with the storage system at any
moment? (Choose two.)

• A. MyISAM
• B. NDB
• C. MEMORY
• D. ARCHIVE
• E. InnoDB

Question 2

Your MySQL installation is running low on space due to binary logs. You need to reduce your log
space usage urgently.
Which two sets of actions when completed will accomplish this? (Choose two.)

• A. Use SET GLOBAL binlog_expire_logs_seconds=<value> and restart the server.
• B. Set binlog_expire_logs_seconds in my.cnf.
• C. Set binlog_expire_logs_seconds = 0 in my.cnf and restart the server.
• D. Use SET PERSIST binlog_expire_logs_seconds=<value>.
• E. Use PURGE BINARY LOGS to <binlog_name>.
• F. Use SET GLOBAL binlog_expire_logs_seconds=<value> and run the FLUSH BINARY LOGS command.

Question 3

A colleague complains about slow response time on your website.
Examine this query and output:

What is the most likely cause for the high number of lock waits?

• A. You use the MyISAM storage engine for most common tables.
• B. You use the InnoDB storage engine and statements wait while data is inserted.
• C. The Innodb Buffer pool is full.
• D. Your table accesses wait for the operating system level flush.

Question 4

You have a MySQL system with 500 GB of data that needs frequent backups.
You use a mix of MyISAM and InnoDB storage engines for your dat
a. Examine your backup requirement:
The MySQL system being backed up can never be unavailable or locked to the client applications.
The recovery from the backup must work on any system.
Only 1 hour of data can be lost on recovery of the backup.
Which option fulfills all backup requirements?

• A. Take a physical backup of the MySQL system.
• B. Use the Clone Plugin to copy the data to another MySQL system.
• C. Take a logical backup of the MySQL system.
• D. Take your backup from a slave of the MySQL system.

Question 5

A MySQL server is monitored using MySQL Enterprise Monitors agentless installation.
Which three features are available with this installation method? (Choose three.)

• A. MySQL Replication monitoring
• B. network-related information and network characteristics
• C. MySQL Query Analysis data
• D. CPU utilization
• E. security-related advisor warnings
• F. operating system memory utilization
• G. disk usage and disk characteristics including disk advisors warnings

Question 6

You are using mysqlcheck for server maintenance.
Which two statements are true? (Choose two.)
A. The mysqlcheck --check --all-databases command takes table write locks while performing a series
of checks.
B. The mysqlcheck --optimize --all-databases command reclaims free space from table files.
C. The mysqlcheck --repair --all-databases command can repair an InnoDB corrupted table.
D. The mysqlcheck command can be renamed mysqlrepair so that it repairs tables by default.
E. The mysqlcheck --analyze --all-databases command performs a series of checks to spot eventual
table corruptions.

Question 7

Examine this command and output:

Which two options will improve the security of the MySQL instance? (Choose two.)

• A. Remove group read/write privileges from the private_key.pem file.
• B. Remove world read privileges from the server-cert.pem certificate file.
• C. Change the group ownership of the mysql directory to the mysql user group.
• D. Remove world read privileges from the public_key.pem file.
• E. Change the parent directory owner and group to mysql.
• F. Remove the world read/execute privilege from the accounting directory.

Question 8

Examine this command, which executes successfully:
cluster.addInstance(<user>@<host>:<port>, {recoveryMethod: clone})
Which three statements are true? (Choose three.)

• A. The account used to perform this recovery needs the BACKUP_ADMIN privilege.
• B. A target instance must exist, then it will be provisioned with data from an instance already in the cluster and joined to the cluster.
• C. InnoDB tablespaces outside the datadir are able to be cloned.
• D. It is always slower than {recoveryMethod: ‘incremental’}.
• E. A new instance is installed, initialized, and provisioned with data from an instance already in the cluster and joined to the cluster.
• F. InnoDB redo logs must not rotate for the duration of the execution; otherwise, the recovery will fail.

Question 9

Which three settings control global buffers shared by all threads on a MySQL server? (Choose three.)

• A. sort_buffer_size
• B. key_buffer_size
• C. table_open_cache
• D. read_buffer_size
• E. innodb_buffer_pool_size
• F. tmp_table_size

Question 10

You reconfigure and start a slave that was not replicating for several days.
The configuration file and CHANGE MASTER command are correct. Examine the GTID information
from both master and slave:

Which statement is true?

• A. Replication will fail because the slave has purged more aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa transactions than the master.
• B. Replication will fail because the master does not have the required transaction with bbbbbbbb- bbbb- bbbb-bbbb-bbbbbbbbbbbb GTIDs in its binary logs.
• C. Replication will fail because the master has already purged transactions with cccccccc-cccc-cccc- cccc-cccccccccccc GTIDs.
• D. Replication will fail because of inconsistent numbers in cccccccc-cccc-cccc-cccc-cccccccccccc GTIDs.
• E. Replication will work.

Question 11

Your MySQL server was upgraded from an earlier major version.
The sales database contains three tables, one of which is the transactions table, which has 4 million
rows.
You are running low on disk space on the datadir partition and begin to investigate.
Examine these commands and output:

Which two statements are true? (Choose two.)

• A. Executing SET GLOBAL innodb_row_format=COMPRESSED and then ALTER TABLE transactions will free up disk space.
• B. Executing ALTER TABLE transactions will enable you to free up disk space.
• C. Truncating the sales and leads table will free up disk space.
• D. Truncating the transactions table will free up the most disk space.
• E. The transactions table was created with innodb_file_per_table=OFF.

Question 12

An attempt to recover an InnoDB Cluster fails.
Examine this set of messages and responses:
host3:3377 ssl JS > dba.rebootClusterFromCompleteOutage() Reconfiguring the default cluster from
complete outage
The instance host1:3377' was part of the cluster configuration. Would you like to rejoin it to the
cluster? [y/N]: y
The instance host2:3377 was part of the cluster configuration. Would you like to rejoin it to the
cluster? [y/N]: y
Dba.rebootClusterFromCompleteOutage: The active session instance isnt the most updated in
comparison with the ONLINE instances of the Clusters metadat
a. Please use the most up to date instance: host1:3377. (RuntimeError)
Which statement is true?

• A. The instance deployed on host3 must be rebuilt with a backup from the primary instance.
• B. The cluster is running and there is at least one ONLINE instance.
• C. The instance deployed on host3 must be synchronized from a donor deployed on host1 by using the command cluster.addInstance(host1:3377).
• D. It is possible to determine the most up-to-date instance by comparing different global transaction identifier (GTID) sets with GTID_SUBSET(set1,set2).
• E. The active session instance is invalid and must be re-created by using the command shell.connect (host3:3377).

Question 13

Which three actions are effective in capacity planning? (Choose three.)

• A. buying more RAM
• B. monitoring OS resources for patterns
• C. adding circular replication nodes for increased DML capability
• D. buying more CPU
• E. buying more disk
• F. basing expected growth on an average of the last 3 years
• G. consulting the application team about any future projects and use
• H. upgrading to the latest application version

Question 14

Examine this command, which executes successfull
mysqlbackup --defaults-file=/backups/server-my.cnf --backup-dir=/backups/full
copy-back
Which statement is true about the copy-back process?

• A. The copy-back process is used to overwrite a new backup over an existing backup.
• B. It restores files from the data directory to their original MySQL server locations.
• C. It restores files from the backup directory to their original MySQL server locations.
• D. The copy-back process makes inconsistent backups.

Question 15

Examine these statements, which execute successfully:
TRUNCATE test; BEGIN;
INSERT INTO test(id, name) VALUES(1, Hello); ROLLBACK;
SELECT id FROM test;
Which three storage engines would return a nonempty recordset for the test table when executing
the statements? (Choose three.)

• A. NDB
• B. ARCHIVE
• C. InnopB
• D. BLACKHOLE
• E. MEMORY
• F. MyISAM