Apa iku stored procedures lan kapan sampeyan kudu nggunakake?

Question

Accepted Answer

A **stored procedure** yaiku set saka SQL statements (lan procedural logic) sing disimpen ing database lan dieksekusi kanthi jeneng. Iki njalanake logic *ing* database tinimbang ing application code. Dheweke duwe benefit sing nyata nanging uga trade-off sing signifikan, dadi kapan nggunakake dheweke yaiku keputusan design sing genuine.

## A stored procedure

```sql
-- define a procedure that encapsulates logic in the database
CREATE PROCEDURE transfer_funds(from_id INT, to_id INT, amount DECIMAL)
LANGUAGE plpgsql AS $$
BEGIN
  UPDATE accounts SET balance = balance - amount WHERE id = from_id;
  UPDATE accounts SET balance = balance + amount WHERE id = to_id;
  -- can include logic: conditionals, loops, error handling, transactions
END;
$$;

CALL transfer_funds(1, 2, 100);   -- execute by name
```

A stored procedure ndandani SQL lan procedural logic (variables, conditionals, loops, error handling) menyang database routine sing jeneng lan bisa digunakake maneh. Functions padha nanging mbali value.

## Potential benefits

```text
✓ Performance — runs IN the database (no round-trips for multi-step logic); precompiled
✓ Reduced network traffic — one call vs many queries from the app
✓ Reusability — shared logic callable from multiple applications/clients
✓ Security — grant EXECUTE on a procedure without granting table access; reduces
  injection surface (parameterized)
✓ Consistency — centralize critical logic so all clients use the same implementation
```

## The significant trade-offs (kenapa akeh sing ngindhari dheweke saiki)

```text
✗ Business logic in the DATABASE → harder to version-control, test, and maintain
  (logic split between app code and the database)
✗ Database-specific (PL/pgSQL vs T-SQL vs PL/SQL) → less portable, vendor lock-in
✗ Harder to debug than application code; weaker tooling
✗ Scaling — the database is often the hardest tier to scale; pushing logic there
  can increase its load
✗ Modern apps often prefer logic in the application layer (testable, portable, versioned)
```

## Kapan nggunakake dheweke

```text
✓ Performance-critical data-intensive operations (heavy multi-step DB logic, batch jobs)
✓ Logic that MUST be enforced at the DB level across multiple clients
✓ Reducing round-trips for operations involving many queries
✗ AVOID putting general business logic in procedures by default — modern practice
  usually favors the application layer (better testing, versioning, portability)
```

## Mengapa iku penting

Ngreti stored procedures — kalebu trade-off-ne — yaiku pengetahuan sing valuable amarga dheweke mewakili pilihan architectural sing genuine kanthi benefit nyata lan drawback nyata, lan ngreti *kapan* nggunakake dheweke (lan kapan ora) nyerminake mature judgment.

Stored procedures bisa nandhangi **performance benefits** (njalanake multi-step logic ing database ngindhari network round-trips), reduced network traffic, reusability utawa clients, security (menehi execute tanpa table access), lan centralized consistency — nggawake dheweke appropriate kanggo performance-critical data-intensive operations, batch processing, lan logic sing kudu dienforced ing database level utawa multiple applications.

Namun, ngreti **significant trade-off** uga penting lan nyerminake modern practice: nglumpukake business logic ing database nggawake luwih angel kanggo version-control, test, lan maintain (pamisah logic antara app lan database), ngubengi sampeyan marang procedural language database sing spesifik (PL/pgSQL, T-SQL, PL/SQL — ngurangan portability), luwih angel debug, lan nambah load marang database tier (asring paling angel kanggo scale).
". Dadi roukohe, **modern application development asring milih tetep business logic ing application layer** (testable, portable, version-controlled) tinimbang ing stored procedures.

Key insight yaiku **judgment kapan nggunakake dheweke** — appropriate kanggo specific performance-critical utawa DB-level-enforcement needs, nanging generally dihindhari minangka default kanggo business logic.

Semono stored procedures common ing akeh systems (utamane enterprise/legacy), lan semono ngreti both benefit lan trade-off-ne (lan modern lean marang application-layer logic) yaiku apa sing nggawe sound architectural decisions, ngreti stored procedures yaiku valuable senior-level knowledge sing nuduhake ability kanggo ngimbangi database-side vs application-side logic — meaningful design consideration lan topic sing nyerminake architectural maturity.