Quick Reference Sheets

Create one-page summaries for each major topic:

DBMS Architecture Sheet

┌─────────────────────────────────────┐
│ DBMS ARCHITECTURE                   │
├─────────────────────────────────────┤
│ • Single-tier: Application + DB on  │
│   same machine                      │
│                                     │
│ • Two-tier: Client ↔ Server         │
│   - Client: UI + Application logic  │
│   - Server: Database                │
│                                     │
│ • Three-tier:                       │
│   - Presentation (UI)               │
│   - Application (Business Logic)    │
│   - Database (Data Storage)         │
│                                     │
│ ADVANTAGES:                         │
│ • Data independence                 │
│ • Data integrity                    │
│ • Concurrent access                 │
│ • Security                          │
│ • Reduced redundancy                │
└─────────────────────────────────────┘

Normalization Sheet

┌─────────────────────────────────────┐
│ NORMALIZATION                       │
├─────────────────────────────────────┤
│ • 1NF: Atomic values, no repeating  │
│   groups                            │
│                                     │
│ • 2NF: In 1NF + no partial          │
│   dependencies on PK                │
│                                     │
│ • 3NF: In 2NF + no transitive       │
│   dependencies                      │
│                                     │
│ • BCNF: For every FD X→Y, X must be │
│   a superkey                        │
│                                     │
│ FUNCTIONAL DEPENDENCY (FD):         │
│ • X→Y means Y is functionally       │
│   dependent on X                    │
│ • If we know X, we know Y           │
└─────────────────────────────────────┘

PL/SQL Quick Reference

┌─────────────────────────────────────┐
│ PL/SQL ESSENTIALS                   │
├─────────────────────────────────────┤
│ STRUCTURE:                          │
│ DECLARE                             │
│   -- Variable declarations          │
│ BEGIN                               │
│   -- Executable statements          │
│ EXCEPTION                           │
│   -- Exception handlers             │
│ END;                                │
│                                     │
│ TRIGGER SYNTAX:                     │
│ CREATE [OR REPLACE] TRIGGER name    │
│ {BEFORE|AFTER|INSTEAD OF} event     │
│ ON table_name                       │
│ [FOR EACH ROW]                      │
│ [WHEN condition]                    │
│ BEGIN                               │
│   -- trigger body                   │
│ END;                                │
│                                     │
│ FUNCTION vs PROCEDURE:              │
│ • Function MUST return a value      │
│ • Procedure does NOT return value   │
└─────────────────────────────────────┘

Cursor Reference

┌─────────────────────────────────────┐
│ CURSOR ATTRIBUTES                   │
├─────────────────────────────────────┤
│ • %ISOPEN: TRUE if cursor is open   │
│ • %FOUND: TRUE if row was fetched   │
│ • %NOTFOUND: TRUE if no row fetched │
│ • %ROWCOUNT: Number of rows fetched │
│                                     │
│ EXPLICIT CURSOR:                    │
│ DECLARE                             │
│   CURSOR cur_name IS select_stmt;   │
│ BEGIN                               │
│   OPEN cur_name;                    │
│   FETCH cur_name INTO variables;    │
│   CLOSE cur_name;                   │
│ END;                                │
│                                     │
│ IMPLICIT CURSOR:                    │
│ • Automatically created for DML     │
│ • Referenced as SQL%attribute       │
└─────────────────────────────────────┘

Memory Techniques

Mnemonic Devices

• ACID: Atomicity, Consistency, Isolation, Durability
• FCIP: Functions return values, Cursors have attributes, Implicit cursors use SQL%, Procedures use parameters
• BAIT: BEFORE, AFTER, INSTEAD OF Triggers
• 123N: 1NF, 2NF, 3NF for remembering normal forms progression

Topic Associations

Connect related concepts to strengthen memory:

• Normalization ↔ Functional Dependencies ↔ Keys
• Triggers ↔ Events ↔ DML Operations