Tables: The Building Blocks of Relational Databases
- Definition and Purpose: Tables represent entities or concepts in your data model. Each table stores information about a specific type of object (customers, products, transactions, etc.).
- Naming Conventions: Best practices for naming tables (singular vs. plural, prefixing, etc.)
- Table Properties: Understanding table characteristics such as storage engines, collation, and compression options
- Temporary vs. Permanent Tables: When and how to use each type
- System Tables vs. User Tables: Differentiating between database-managed tables and user-created tables
- Partitioned Tables: Introduction to table partitioning for performance optimization
Columns and Data Types
- Column Definition: Understanding attributes that define columns (name, data type, constraints)
- Data Type Selection: Choosing appropriate data types for different kinds of information
- Numeric types (INT, DECIMAL, FLOAT, etc.)
- Character types (CHAR, VARCHAR, TEXT)
- Date/time types (DATE, DATETIME, TIMESTAMP)
- Binary types (BLOB, BINARY)
- Special types (JSON, XML, spatial data types)
- Column Constraints: NOT NULL, DEFAULT, CHECK, UNIQUE
- Computed/Generated Columns: Creating columns based on expressions
- Column Storage and Performance Implications: How column choices affect storage and query speed
Rows: The Actual Data
- Row Structure: How data is physically stored within rows
- Row Size Limitations: Understanding maximum row sizes in different database systems
- Row Operations: INSERT, UPDATE, DELETE conceptual overview
- Row Versioning: How databases track changes for concurrency control
- Row Locking: Introduction to how databases manage concurrent access to rows
- Statistics and Cardinality: How the number of rows affects query performance
Keys: Ensuring Data Integrity and Relationships
Primary Keys
- Definition and Importance: Unique identifier for each record in a table
- Selection Criteria: Guidelines for choosing effective primary keys
- Natural vs. Surrogate Keys: Using existing data vs. system-generated identifiers
- Composite Primary Keys: When and how to use multiple columns as a primary key
- Implementation Options: AUTO_INCREMENT, IDENTITY, Sequences, UUIDs
- Performance Considerations: Indexing, clustering, and storage implications
Foreign Keys
- Purpose and Function: Establishing and enforcing relationships between tables
- Referential Integrity: Ensuring data consistency across related tables
- Constraint Actions: CASCADE, SET NULL, SET DEFAULT, RESTRICT, NO ACTION
- One-to-Many, Many-to-Many, and One-to-One Relationships: Implementation patterns
- Self-Referencing Foreign Keys: Handling hierarchical data
- Performance Implications: How foreign keys affect INSERT, UPDATE, and DELETE operations
- Deferrable Constraints: Delaying constraint checks until transaction commit
Practical Applications and Best Practices
- Normalization and Denormalization: Balancing data integrity and performance
- Entity-Relationship Modeling: Designing tables and relationships
- Indexing Strategies: Optimizing key columns for query performance
- Data Migration Considerations: Moving data while maintaining relationships
- Versioning and Temporal Data: Managing historical data with effective key strategies
- Scale Considerations: How key choices affect database scalability
Last modified: Thursday, 10 April 2025, 3:53 PM