Repository Use Cases and CRUD

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Repository Use Casesand CRUD
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Repository Use Cases

• There are four main operations that are commonly
  performed on repositories, whether they are files
  or true databases
• Create create and add an item to the repository
• Read view a repository item
• Update edit a repository item
• Delete remove a repository item
• These operations are collectively known as CRUD.
• In most applications, there will be at least one
  CRUD use case. For example, this semesters
  project may include a CRUD use case for
  maintaining the repository of CS, IS, and GEP
  courses. You may also have other repositories
  that require maintenance.
• The following slides show a suggested way in
  which you can handle CRUD use cases in your SRS.

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Suggested Approach for Our Class

• Have a top-level use case called something like
  Maintain X Repository (e.g., Maintain Accounts
  Repository)
• Write a corresponding specification for this use
  case. The use case should include viewing the
  repository as one of the steps in the Main
  Scenario.
• Draw a sub-use case diagram for Maintain X
  Repository that has three extensions for
• creating an item (e.g., Create Account) in the X
  repository,
• editing an item in the X repository, and
• deleting an item from the X repository.
• For our class, you do not need to have a
  specification for each of these three extended
  use cases. (In industry, these might need to be
  written.)

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system name
Top-level use case diagram with a CRUD use case
1 Use Case 1 Name
2 Use Case 2 Name
3 Maintain X Repository
n Use Case n Name
CRUD use case
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CRUD Use Case Specification
Number 3 3
Name Maintain X Repository Maintain X Repository
Summary User adds to, edits, or deletes from X repository User adds to, edits, or deletes from X repository
Priority 5 5
Preconditions precondition precondition
Postconditions postcondition postcondition
Primary Actor(s) role name role name
Secondary Actor(s) external system name external system name
Trigger User chooses to maintain X repository User chooses to maintain X repository
Main Scenario Step Action
1 System displays repository
2 User performs repository operation
3 System updates repository
Extensions Step Branching Action
2a Use Case 3a Create Y
2b Use Case 3b Edit Y
2c Use Case 3c Delete Y
Open Issues open issue
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CRUD Sub-Use Case Diagram
3c Delete Y
3 Maintain X Repository
3b Edit Y
3a Create Y
Y is one of the items in the X repository