database

Database transactions ensure data integrity when multiple operations must succeed or fail together. I use @transaction.atomic on views or functions to wrap them in a transaction. For partial rollbacks, I use transaction.atomic() as a context manager a

Transactions ensure data consistency through ACID properties. Atomicity guarantees all-or-nothing execution. Consistency maintains database constraints. Isolation prevents concurrent transaction interference. Durability persists committed changes. I u

Spring Data JPA eliminates boilerplate DAO code with repository interfaces. I extend JpaRepository to get CRUD methods automatically—save, findById, findAll, delete. Custom query methods use method naming conventions—findByEmailAndActiveTrue generates

Seeders populate databases with test or initial data. I create seeder classes in database/seeders with a run() method. The DatabaseSeeder orchestrates other seeders. For large datasets, I use factories with factory()->count(100)->create() for pe

Partitioning splits large tables into smaller physical pieces. Range partitioning divides by value ranges—dates, IDs. List partitioning groups by specific values—regions, categories. Hash partitioning distributes evenly across partitions. I use partit

Constraints enforce data integrity at the database level. PRIMARY KEY ensures uniqueness and identifies rows. FOREIGN KEY maintains referential integrity. NOT NULL prevents null values. UNIQUE prevents duplicates. CHECK validates data conditions. DEFA

Performance monitoring identifies slow queries and bottlenecks. I use EXPLAIN ANALYZE to profile query execution. pgstatstatements tracks query statistics over time. Slow query logs capture problematic queries. Query execution time, I/O, and buffer us

Proper indexing is the difference between millisecond and multi-second query response times. I add indexes to foreign keys automatically since Rails doesn't do this by default, and I create composite indexes for common query patterns that filter on mu

The atomic decorator/context manager ensures all-or-nothing database operations. I wrap related operations in @transaction.atomic or with transaction.atomic() blocks. If any operation fails, the entire transaction rolls back. This prevents partial dat

Data import/export moves data between systems. I use COPY for bulk operations—orders of magnitude faster than INSERT. CSV format balances simplicity and performance. Binary format is faster but less portable. Streaming import handles large files witho

Transactions ensure that multiple database operations either all succeed or all fail together, preventing partial updates that leave data in inconsistent states. Rails provides ActiveRecord::Base.transaction which wraps a block of code in a database t

JSONField stores structured data without creating separate tables. I use it for settings, metadata, or varying attributes. Django provides database-level JSON operations via lookups like __contains, __has_key. For PostgreSQL, I get native JSON operato