The cornerstone of all Nessos applications is not just an ordinary Object-Relational Mapper. It provides:

 

• Visual design of class hierarchies
• Automated generation of ER model from class hierarchies
• Automated generation of SQL and C# source code
• Visualization of ER model
• Automated reconstruction of class hierarchies of .NET assembly through Reflection
• Metadata-based persistence
• Application development independent of RDMBS in use
• Application development using object-oriented techniques and functional programming
• Native support of standard business objects 
  • Parameters model 
  • Security model
• Test-driven development through Unit Tests
• Support for Microsoft Visual Studio 2005, 2008

 

 

Vizualization of relational model

Automated generation of SQL of Database that corresponds to the Business Object Model

 Detailed Technical Description of Nessos Object-Relational Mapper Features

• Mapping
  • ActiveRecord based (1-1)
  • Table - Class
  • Property – Column
  • Type of relations (1-1, 1-n, n-n)
  • Single Table Inheritance
  • Attribute based mapping – sensible default conventions
  • Special support for mapping localizable columns
• Query
  • (IQuery) Internal DSL for expressing statically typed queries
  • Aggregate (SUM, AVG, MAX etc)
  • Sub queries
  • Functions (Trim, SubString, Abs etc)
  • Support for joins (inner join, left outer join)
  • Support for order by-group by clauses
  • Support for Localization parameters in Select and Where clauses
  • Polymorphic queries
  • Flexibility in result types
    • Strongly typed collections
    • DataTable – for support in scenarios with flexible projections in reporting scenarios
  • Custom parameterized SQL for not-supporting scenarios
• Base Type (BusinessObject) for one stop shop experience
  • Object tracking management
  • Transparent object Persistence
  • Common retrieval methods
• Session Management
  • Light-Weight Session Scope with transaction semantics similar to TransactionScope
  • Support for implicit
    • Lazy loading
    • Transaction Management
    • Caching
• Loading
  • Lazy Loading
    • Implicit - Automatic loading on member-Collection dereferences, plus caching inside session scopes
    • Explicit loading with the use of Refresh methods
  • Eager Loading (In order to avoid N+1 selects and the problem of multiple Left outer joins we use one select query for each depth level and at the end we reconstruct the object graph)
    • Based On Depth
      • Unidirectional deepening for scenarios that demand no circle references(like Xml Serialization)
    • Based On Dereference Paths from Root
• Support n-Tier scenarios
  • Self-tracking Business Objects
  • Silverlight support – WCF
  • Winforms support – ASMX
• Concurrency management
  • Optimistic concurrency with the use of TimeStamp Columns
• Transaction Support
  • Explicit API for begin-complete-rollback transactions
  • Implicit support (inside Session Scopes) for begin-complete-rollback transactions
• Localization
  • Flexible String Localization with the use of special container type
  • Attribute decorated enums
• Validation
  • Attribute based (Presence, RegEx etc)
  • Per Business Object cascading Validation
  • Flexible Rule set Validations
• Customization-Configuration
  • IoC based configuration
  • Multiple available Loggers for injection
• Multiple OS/Platforms
  • Mono support
• Multiple Databases Support
  • SQL Server 200x, Oracle, PostgreSQL