MySQL

1. Data Types

   Numeric, string, date and time, JSON and spatial column types, storage requirements and choosing appropriate types.

2. SQL Statements

   DDL, DML and transactional statements, SELECT, INSERT ... ON DUPLICATE KEY UPDATE, joins and subqueries.

3. Character Sets and Collations

   utf8mb4, collations, comparison and sorting rules, connection character sets and Unicode support.

4. The InnoDB Storage Engine

   InnoDB architecture, clustered indexes, buffer pool, tablespaces, redo and undo logs, doublewrite buffer and crash recovery.

5. Transactions and Isolation Levels

   READ COMMITTED, REPEATABLE READ and SERIALIZABLE isolation, consistent nonlocking reads and MVCC in InnoDB.

6. InnoDB Locking

   Record, gap and next-key locks, intention locks, deadlocks, SELECT FOR UPDATE and locking reads.

7. Indexes and Optimization of Indexing

   B-tree and hash indexes, multi-column and covering indexes, invisible indexes, index prefixes and fulltext indexes.

8. Query Optimization and EXPLAIN

   EXPLAIN output, join algorithms, optimizer hints, statistics, query execution plans and tuning SQL statements.

9. JSON Data Type

   Native JSON column type, path expressions, JSON functions, generated columns and indexing JSON values.

10. Partitioning

    Range, list, hash and key partitioning, partition pruning and partition management.

11. Replication

    Binary log, source and replica threads, GTIDs, row versus statement formats, semisynchronous replication and replication lag.

12. Group Replication and InnoDB Cluster

    Paxos-based group replication, single-primary and multi-primary modes, conflict detection, InnoDB Cluster and MySQL Router.

13. Backup and Recovery

    Logical and physical backups, mysqldump, point-in-time recovery using binary logs and consistent backups.

14. Performance Schema and sys Schema

    Instrumentation of waits, statements and locks, monitoring server performance and diagnosing slow queries.

15. Security and Access Control

    Accounts and privileges, roles, authentication plugins, TLS connections and encryption at rest.

16. Server Administration

    System variables, configuration, logs including slow query log, server components and connection management.

17. Stored Programs, Views and Triggers

    Stored procedures, functions, triggers, events and views.

Each section links to the official page. Titles and summaries by Extra Credit; the docs belong to their authors.

Source: endoflife.date

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