Setting general_log to ON enables query logging. log_queries, log_output, and log_queries_on are incorrect or incomplete settings for this purpose.

Row-based replication logs actual row modifications, improving data consistency by avoiding non-deterministic statement execution that can lead to replica drift.

The mysql.table_constraints table contains index and constraint metadata inside the Data Dictionary. The other options are not valid Data Dictionary tables.

The SHOW GRANTS statement lists all privileges assigned to a user. SHOW PRIVILEGES FOR is not a valid command, and querying mysql.privileges or mysql.user directly is not the recommended method.

MySQL 8.0 uses AES-256 as the default encryption algorithm for InnoDB tablespace encryption, providing a high level of security. RC4, 3DES, and Blowfish are either outdated or not supported for this purpose.

Encrypting backup files using SSL or other encryption methods ensures that backup data remains secure, even if stored outside of MySQL. Storing backups in an unencrypted format or adjusting timing does not directly secure the backup data.

A Primary-Replica topology with multiple read replicas is commonly used for scalability and high availability, ensuring that reads are distributed efficiently while keeping a single primary for consistency.

The InnoDB Storage Engine Subsystem is responsible for tablespace management, transaction processing, and ACID compliance in MySQL 8.0. It handles data storage through file-per-table or shared tablespaces and manages buffer pools for performance optimization. The Storage Engine Interface acts as a bridge but does not handle storage directly. The Data Dictionary Module stores metadata but not user data.

The innodb_redo_log_capacity variable determines the total redo log space available for transactions before logs are flushed. innodb_log_file_size used to control this in previous versions but is now deprecated. innodb_undo_tablespaces manages rollback segments, and innodb_buffer_pool_size affects caching of data and indexes, not transaction logs.

In multi-primary Group Replication, MySQL uses conflict detection rules to avoid conflicting writes across nodes. Single-threaded replication, commit timeouts, and disabling binlog checksums do not improve consistency in a multi-primary environment.

Using replication-based migration allows traffic to be switched from old to new instances without service interruption. Other methods risk downtime due to transaction mismatches.

The –parallel-threads-set option specifies how many threads to use in mysqlpump for parallel execution. –default-worker-count is incorrect. –thread-concurrency-opt does not exist, and –jobs-processors-list is unrelated.

Multisource replication allows a single replica server to receive changes from multiple primary servers. This requires defining separate replication channels, each corresponding to a different source. Unlike traditional replication, relay logs are not unique per source, semi-synchronous replication is optional, and GTIDs are managed globally, not per thread.

In MySQL replication, using FLUSH TABLES WITH READ LOCK ensures consistent backups by preventing writes. Stopping binary logging disrupts replication consistency. Flushing table statistics does not ensure data integrity, and Restarting buffer pool affects memory, not backups.

To check recorded firewall rules for a user, administrators can query mysql.firewall_whitelist. The other options are not valid MySQL commands.

Setting bind_address=‘0.0.0.0‘ makes MySQL accessible from all IP addresses, increasing the risk of unauthorized access. max_connections affects performance but is not a security issue. thread_cache_size and net_read_timeout manage connection efficiency but do not introduce security vulnerabilities.

Enabling group_replication_start_on_boot ensures that nodes automatically restart replication after failure recovery. The other settings do not enable automatic recovery.

The dba.configureInstance() command configures an instance to meet the requirements for joining an InnoDB Cluster. It does not check consistency, modify election rules, or synchronize binary logs.

MySQL logs startup failures in /var/log/mysql/mysql-error.log, helping administrators troubleshoot errors. The other options do not represent valid MySQL error log files.

TLSv1.3 is the latest and most secure version, offering faster handshakes and stronger encryption than TLSv1.2. TLSv1.1 and TLSv1.0 are considered obsolete and insecure.

A covering index contains all columns needed for a query, allowing MySQL to avoid reading the actual table (known as Index-Only Scan). This greatly improves performance by reducing I/O operations. They do not replace foreign keys, nor do they store only pointers. While they can sometimes improve JOINs, that is not their primary benefit.

In MySQL 8.0, SHOW REPLICA STATUS replaces SHOW SLAVE STATUS to provide detailed replication diagnostics, including thread states, lag, and errors. The master status command only shows binary log details, while the processlist command displays all active threads, not just replication-related ones.

In Group Replication, the Group Communication System (GCS) detects conflicts and applies transaction rules. There is no Global Transaction Handler, and InnoDB does not resolve conflicts independently. The Primary Election Process determines leadership, not conflicts.

The secure_file_priv setting restricts the directories that MySQL can use for importing and exporting files, helping to prevent unauthorized access to sensitive data directories. The other options do not exist in MySQL 8.0.

The query cache stores results of SELECT queries, so identical queries can retrieve data faster without re-executing them. It does not store query plans or reduce locks.

The MySQL binary log (mysql-bin-logs.log) records all SQL statements that modify the database for replication and recovery. The other options refer to unrelated or non-existent log files.

The MySQL server process ID (PID) is stored in /var/run/mysql/mysql.pidfile, allowing system tools to manage the server process. The other options do not refer to valid MySQL PID storage locations.

The File-Per-Table Mode enables MySQL to reclaim space efficiently by allowing table truncation or dropping to shrink .ibd files. The Shared Tablespace does not reclaim space well, Temporary Tables store non-persistent data, and Page Compression reduces disk usage but does not reclaim space.

The events_statements_summary table in performance_schema tracks statement execution metrics, including index usage. table_io_waits_summary records I/O wait times, but not index details. table_lock_waits_summary focuses on lock waits, while table_statistics_summary does not specifically track index usage.

The mysqlbinlog utility can back up binary logs remotely by streaming data. mysqldump does not handle binary logs. mysqlpump does not support binary log backups, and cp does not ensure log consistency.

A Chroot Jail can be used to isolate MySQL from the broader operating system, ensuring that MySQL can only access the files and directories designated within the jail. Both AppArmor and SELinux provide additional security but are not as directly focused on this specific environment isolation.

In MySQL replication, the I/O thread retrieves binary logs from the primary server and stores them as relay logs on the replica. The SQL thread then reads the relay logs and applies transactions. The Coordinator and Worker threads do not handle relay logs directly.

The mysql.firewall_whitelist table contains allowed SQL statements for users configured in MySQL Enterprise Firewall. The other tables do not exist in the MySQL security system.

An Exclusive Lock in InnoDB prevents other transactions from reading or modifying the locked row, making it the primary cause of contention. Shared Locks do not block reads, Metadata Locks impact schema changes, and Gap Locks occur in specific transaction isolation levels.

The Threads_connected status variable reflects the number of currently active client connections. The other variables do not exist or provide unrelated metrics.

MySQL Router dynamically fetches cluster metadata to automatically route traffic. Manually modifying routing tables, static node assignments, or restarting connections are not required for failover.

The ALTER USER ‘user‘@‘host‘ REQUIRE SSL command forces the user to use an SSL connection. The other options are either incorrect syntax or unsupported by MySQL 8.0.

The REAL_ESCAPE_STRING() function in MySQL escapes special characters, making input safe by preventing SQL injection attacks. Other functions like QUOTE() don’t provide the same level of protection.

MySQL does not provide automatic conflict resolution in multisource replication. The best approach is to design applications to avoid conflicting writes across multiple sources. Delayed replication, row-based formats, and external tools may help, but they do not prevent conflicts at the source level.

The dba.rebootClusterFromCompleteOutage() command automatically recovers the cluster when all nodes fail. Other options, such as resetting metadata, validating instances, or resetting topology, do not perform full recovery.

The innodb_file_per_table setting determines whether each InnoDB table has its own tablespace or shares a global tablespace, directly affecting storage expansion strategies. Other parameters do not impact database size growth.

Assigning privileges to the PUBLIC role means all users can access those privileges, creating a major security risk. Using roles helps manage permissions effectively, restricting access to system tables enhances security, and table-level privileges limit unnecessary access.

The error log records failed authentication attempts, plugin errors, and permission issues, making it essential for security auditing. The other logs do not focus on authentication failures.

The MySQL Data Dictionary System stores schema, table, column, and index metadata, replacing .frm, .TRG, and .TRN files. The other options do not exist or refer to different concepts.

The /etc/mysql/my.cnf-defaults file is typically used to configure MySQL settings on Linux. The other options are incorrect file paths or non-existent configurations.

The MySQL Prepared Statement Cache stores compiled SQL statements, reducing parsing overhead for repeated queries. The other options do not exist in MySQL or serve different purposes.

To enable encryption for an InnoDB table in MySQL 8.0, you use ALTER TABLE ENCRYPTION=‘Y‘;. This ensures the tablespace is encrypted using a key from the configured keyring plugin. The SET GLOBAL innodb_encrypt=ON; command does not exist. ENABLE ENCRYPTION ON TABLE is not a valid SQL statement. Directly modifying system tables (mysql.tables) is not supported for enabling encryption.

Client settings are defined within the [client] section of the my.cnf file, which ensures correct client behavior across various MySQL programs. Other files or sections are not used for client-specific configurations.

MySQL Enterprise Monitor prioritizes query optimization by focusing on execution time, since slow queries have the greatest impact on performance. Other metrics like lock wait times and temporary tables are useful but secondary.

The mysqlbackup –backup command is used in MySQL Enterprise Backup to perform a full database backup. mysqldump –all-databases performs a logical dump. mysqlpump –include-schema is another logical export tool, and mysqlbinlog –save-logs is used for binary log backups.

The InnoDB redo log plays a crucial role in MySQL‘s crash recovery mechanism. Before changes are written to the tablespace files, they are recorded in the redo log to ensure durability and consistency. In the event of a system failure, MySQL can use the redo log to recover committed transactions that were not yet flushed to disk. Unlike the binary log, which is used for replication, the redo log is internal to InnoDB and is essential for ACID compliance.

The FORCE PASSWORD CHANGE option forces users to change their password upon first login. The other options are incorrect or do not exist in MySQL 8.0.

The dba.getCluster().status() function provides a detailed status of an InnoDB Cluster. Checking group_replication status, metadata tables, or binary logs does not provide full recovery information.

The –single-transaction option allows mysqldump to take a consistent snapshot of InnoDB tables without locking them. –disable-keys-option speeds up index rebuilding but does not ensure consistency. –lock-tables-command locks tables but blocks writes. –quick-buffer-enable does not exist.

Using indexes on columns involved in ORDER BY can significantly reduce sorting overhead. Index_merge, GROUP BY, or forcing early execution do not provide similar optimizations in this case.

Multi-threaded replication (MTR) enables parallel execution of transactions on replicas, reducing replication lag, especially on workloads with independent transactions. Group Replication provides high availability but does not address lag directly. Heartbeat events help monitor but do not prevent lag. Read scaling distributes queries but does not impact the replication process.

The slave_parallel_workers option configures multi-threaded replication in MySQL. This setting must be placed in the [mysqld] section to ensure proper execution. Other options, like master_replication, are incorrect.

The performance_schema.events_statements_history table records SQL statements, execution time, and resource consumption. Other tables focus on threads, memory, or connection tracking.

The Alerting System in MySQL Enterprise Monitor detects server anomalies, slow queries, high CPU usage, and replication issues, triggering alerts for administrators. Other components do not generate real-time alerts.

To resume replication from a GTID position, MySQL uses GTID auto-positioning, configured via CHANGE REPLICATION SOURCE TO … SOURCE_AUTO_POSITION = 1. The RESET MASTER and RESET REPLICA ALL commands clear logs but do not position replication, and GTID enforcement ensures consistent logging, not GTID-based resumption.