Explain the difference between packages and standalone procedures in Oracle. What are the benefits of using packages?

**Standalone Procedures**: Individual procedures created separately

- CREATE OR REPLACE PROCEDURE proc_name AS BEGIN ... END;

- Each procedure is independent

- No encapsulation or grouping

**Packages**: Group related procedures, functions, and variables

- Package specification (interface): Public declarations

- Package body (implementation): Private and public code

- Provides encapsulation and namespace management

**Benefits of Packages**:

1. **Encapsulation**: Public vs private members

- Package spec: Public interface

- Package body: Private procedures/variables

- Hide implementation details

2. **Performance**: Entire package loaded into memory

- First call loads entire package

- Subsequent calls use cached package

- Faster than loading individual procedures

3. **Namespace Management**: Avoid naming conflicts

- order_management.create_order

- inventory_management.create_order

- Same procedure name, different packages

4. **Session State**: Package variables persist across calls

- Store session-specific data

- Avoid repeated queries

5. **Easier Maintenance**: Related code grouped together

- All order operations in order_management package

- Easier to find and modify

**Example**:

```sql

-- Package specification

CREATE OR REPLACE PACKAGE order_mgmt AS

PROCEDURE create_order(p_customer_id IN NUMBER);

FUNCTION get_total(p_order_id IN NUMBER) RETURN NUMBER;

END;

-- Package body

CREATE OR REPLACE PACKAGE BODY order_mgmt AS

-- Private variable

v_order_count NUMBER := 0;

-- Private procedure (not in spec)