Session 3 - It's 11 pm, Do you know where your queries are? - Part 1

Eric Farrar, Sybase iAnywhere

Talking about Object Relational Mappers (ORMs) and Active Records - tradeoffs

They are using Ruby here as their example data

ORM difficulties

• Normalization
• Database can only store scalar values
• Add an extra layer of abstraction

Examples of ORMs/Active Records
LINQ
Hibernate
DJango
Ruby on Rails
many more

Trade-offs

Advantages

• easy to learn
• simplifies database creation and management
• No context switching between languages
• Ability to create database agnostic applications
• You don't need know about the database

Disadvantages

• Performance suffers (up to 50% slower) or more
• Often uses lowest-common denominator solution
• concurrency semantics often very difficult
• you don't need to know about the database

...