Myers in the book "Composite structured design"  :
 

An informational-strength module has the following definition:
 

1. It contains multiple entry points.
   
2. Each entry point performs a single specific function.
   
3. All of the functions are related by a concept, data structure, or resource that is hidden within the module.

1. what is entry points of the module?
    
2. and what is ** multiple entry points** of the module?
    
3. a SQL class containing 4 methods: add(), delete(), update(), retentive() has info. cohesion or functional cohesion?
   4)please give me a good example for class having info. cohesion

please answer the above 4 questions?

I try to understand what cohesion means when designing modules. Myers states in his book "Composite structured design":

An informational-strength module has the following definition:

• It contains multiple entry points.
• Each entry point performs a single specific function.
• All of the functions are related by a concept, data structure, or resource that is hidden within the module.

I am not sure to fully understand this definition:

1. what is an entry points of the module?
2. what is multiple entry points for a module?
3. has a SQL class containing 4 methods: add(), delete(), update(), retentive() informational cohesion or functional cohesion?
4. what would be a practical example for a class having informational cohesion?