database

name	Database
description	Standards for database interaction, connection pooling, and repository patterns in Golang.
metadata	{"labels":["golang","database","sql","postgres","repository"],"triggers":{"files":["internal/adapter/repository/**"],"keywords":["database","sql","postgres","gorm","sqlc","pgx"]}}

Golang Database Standards

Priority: P0 (CRITICAL)

Principles

• Prefer Raw SQL/Builders over ORMs: Go structs map well to SQL. ORMs (GORM) can obscure performance. Recommended: sqlc (type-safe SQL generation).
• Repository Pattern: Abstract DB access behind interfaces in internal/port/ (e.g., UserRepository).
• Connection Pooling: Always configure SetMaxOpenConns, SetMaxIdleConns, SetConnMaxLifetime.
• Transactions: Logic requiring ACID MUST use transactions. Pass context.Context everywhere.

Drivers

• PostgreSQL: jackc/pgx (Prefer pgx/v5 for performance and features).
• MySQL: go-sql-driver/mysql.
• SQLite: mattn/go-sqlite3 or modernc.org/sqlite (pure Go).

Anti-Patterns

• Global DB Connection: Do not use global var db *sql.DB. Inject it.
• Ignoring Context: Always use db.QueryContext or db.ExecContext to handle timeouts.
• Leaking Rows: ALWAYS defer rows.Close() and check rows.Err().

References

• Repository Pattern Implementation
• Connection Tuning