mysql

Backups protect against data loss from failures, corruption, or human error. I use full backups for complete database snapshots. Incremental backups save only changes since last backup. Point-in-time recovery restores to specific moments. Logical back

EXPLAIN reveals database execution plans. I use EXPLAIN ANALYZE for actual runtime statistics. Understanding plan nodes—Seq Scan, Index Scan, Nested Loop, Hash Join—guides optimization. Cost estimates predict query expense. Rows estimates show expecte

Indexes dramatically speed up queries but slow down writes. B-tree indexes handle equality and range queries—default for most databases. I create indexes on foreign keys, frequently queried columns, and WHERE/ORDER BY clauses. Composite indexes order

Replication copies data across multiple servers for redundancy and scalability. Master-slave replication has one writable primary, multiple read-only replicas. I use read replicas to scale read-heavy workloads. Master-master allows writes to multiple