1Z0-888 Exam Training Practice Tests (Oracle MySQL 5.7 Database Administrator)]

Question 1

Which statement is correct about how InnoDB storage engine uses disk space?

A. It stores its data, index and undo information in .MYD and .MYI files. B. It stores data in .MYD files and its index and undo information in the common tablespace. C. It stores its data in tablespace file(s). Index and data dictionary details are stored in .FRM files. D. It stores data in .MYD files, index information in .MYI files, and undo information in the common tablespace. E. It stores data, index and undo information in tablespace file(s).

Correct Answer: E

Question 2

Is it true that binary backups always take less space than text backups?

A. Yes, because binary backups only contain data, and not statements required to insert data into the tables. B. No, because text backups can have optimizations, which make them smaller, such as updating many rows at once. C. Yes, because even if InnoDB tables contain many empty pages, text backups have empty INSERT statements for them. D. No, because if InnoDB tables contain many empty pages, they could take more space than the INSERT statements.

Correct Answer: D

Question 3

You have been tasked with creating a QA MySQL instance on a DB host, which already has one large instance in /var/lib/mysql/running as the mysqluser. The MySQL configuration file for the existing instance includes:

The default instance was installed using the OS package manager. The latest binaries for both client and server are already in ENV PATH.
The new instance will run as a different user from the existing instance for security purposes.
You create the new data directory successfully and move on to initialize the new DATADIR.
You verify the output to confirm the operation's success:
[mysqlQA@linux /var/lib/]$ mysqld --initialize --datadir=/var/lib/mysql_QA 2>&1 | tail -n3
2018-05-03T12:16:10.928809Z 0 [ERROR] Could not open file '/var/log/mysqld.log' for error logging:
Permission denied
2018-05-03T12:16:10.928841Z 0 [ERROR] Aborting
[mysqlQA@linux /var/lib/]$
The initialization of the instance has failed.
What would you do to enable the initialization to succeed?

A. Use mysql_install_db. B. Change permissions on /var/log/mysqld.log to allow writes. C. Pass --log-error=/var/lib/mysql_QA/mysqld.log. D. Use --no-defaults to ignore the existing config file in the default PATH.

Correct Answer: A

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Question 4

You have successfully provisioned the latest MySQL 5.7 database instance on a physical host, to be added to an existing farm for use in a modern, high volume, ACID-compliant, OLTP website, which serves hundreds of DML transactions per second.
The default values of which two key variables do you change to ensure seamless operation of the database? (Choose two.)

A. Sort Buffer size B. Binary Log Size C. InnoDB Redo Log Size D. Buffer Pool Size E. Query Cache Size F. Key Buffer Size

Correct Answer: A,F

Question 5

After analysis on the slow query log on a high-end OLTP service, the table identified in the slow queries is:

What are the two most likely reasons for the slowness given this output?

A. The engine type is not appropriate to the application use. B. No indexes are defined. C. Using default values for DATETIME causes table scans. D. Date should be a TIMESTAMP field for better performance. E. The User field is too long for most names.

Correct Answer: A,B

Question 6

Which three are key advantages of standard MySQL replication?

A. enables automatic resync of databases when discrepancies are detected B. is easy to configure and has low performance overhead C. synchronously guarantees identical slave copy D. can easily add slaves for read scaling E. provides arbitrary geographic redundancy with minimal overhead to master F. supports native automatic failover

Correct Answer: A,B,D

Question 7

One of your colleagues is trying to make a change using the mysql command-line client for his or her application session.
The colleague instant messages you this command:
mysql> SET SESSION max_connections = 200;
Why does the command fail?

A. Users can control only the max_user_connections variable. B. max_connections requires the GLOBAL scope. C. max_connections is not a dynamic variable. You need to change the config file and restart the database. D. Its current user does not have the SUPER privilege.

Correct Answer: B

Question 8

You are using replication and the binary log files on your master server consume a lot of disk space. Which two steps should you perform to safely remove some of the older binary log files? (Choose two.)

A. Edit the .index file to remove the files you want to delete. B. Execute the PURGE BINARY LOGS NOT USED command. C. Use the command PURGE BINARY LOGS and specify a binary log file name or a date and time to remove unused files. D. Ensure that none of the attached slaves are using any of the binary logs you want to delete. E. Remove all of the binary log files that have a modification date earlier than today.

Correct Answer: C,D

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Question 9

You have issued this statement:
GRANT PROXY ON 'a' FOR 'b';
When user account 'b' issues a query, the query returns an access denied error.
What could have caused that error?

A. User account 'a' has not been granted permission to access the data being queried. B. User account 'b' has not been granted permission to access the data being queried. C. When connecting, user account 'b' is not entering the correct password for user account 'a'. D. You have not set the proxy_user variable in the configuration file.

Correct Answer: C

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Question 10

You are using GTIDSin replication. You need to skip a transaction with the GTIDof aaa-bbb-ccc-ddd- eee:3on a slave.
Which procedure would you execute from a MySQL prompt?

A.

B.

C.

D.

Correct Answer: C

Oracle MySQL 5.7 Database Administrator - 1Z0-888 Exam Practice Test