Examine these statements and output: 

mysql> GRANT PROXY ON accounting@localhost TO ' '@'%' ; 

mysql> SELECT USER(), CURRENT_USER(), @@proxy_user;

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Which statement is true?

Examine this statement, which executes successfully

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You want to improve the performance of this query: 

SELECT Name 

FROM world.city 

WHERE Population BETWEEN 1000000 AND 2000000; 

Which change enables the query to succeed while accessing fewer rows?

You are having performance issues with MySQL instances. Those servers are monitored with MySQL Enterprise Monitor. Using Query Analyzer, where do you begin to look for problem queries?

You have upgraded the MySQL binaries from 5.7.28 to 8.0.18 by using an in-place upgrade.

 Examine the message sequence generated during the first start of MySQL 8.0.18：

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Which step or set of steps will resolve the errors?

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What is the content of the test folder in the data directory?

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 isn't the most updated in

Comparison with the ONLINE instances of the Cluster's metadata.

Please use the most up to date instance: ' host1:3377'. (RuntimeError)

Which statement is true?

mysql> SHOW FULL PROCESSLIST;

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Examine this query:

SELECT SUM(m.CURRENT_NUMBER_OF_BYTES_USED) AS TOTAL

FROM performance_schema.memory_summary_by_thread_by_event_name m

INNER JOIN performance_schema.threads t

ON m.THREAD_ID = t.THREAD_ID

WHERE t.PROCESSLIST_ID = 10;

What information does this query provide?

mysql> SHOW FULL PROCESSLIST

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mysql> SELECT object_type, object_schema, object_name, lock_type, lock_status, 

owner_thread_id, owner_event_id

 -> FROM performance_schema.metadata_locks WHERE object_schema != 

'performance_schema'

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mysql> SELECT thread_id, processlist_id, processlist_user, parent_thread_id 

-> FROM per formance_schema.threads WHERE processlist_user=' root';

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Which connection ID is holding the metadata lock?