Server-storage interface

components

• one k-object definition table
• many k-object instance tables
• one k-relation definition table
• many k-relation instance tables

operations

write operations

• k-object definition table
  • add k-object definition (insert)
  • modify k-object definition (update)
  • remove k-object definition (delete)

• k-object instance table
  • create k-object instance table
  • drop k-object instance table
  • add instance to k-object instance table
  • modify instance in k-object instance table
  • remove instance from k-object instance table

• k-relation definition table
  • add k-relation definition (insert)
  • modify k-relation definition (update)
  • remove k-relation definition (delete)

• k-relation instance table
  • create k-relation instance table
  • drop k-relation instance table
  • add instance to k-relation instance table
  • modify instance in k-relation instance table
  • remove instance from k-relation instance table

read operations

• select from a single table
  • select from k-object definition table
  • select from k-relation definition table
  • select from k-object instance table
  • select from k-relation instance table

• select from 2 or more tables joined together

protocol

The communication between server and storage consists of requests issued by the server and replies issued by the storage.

requests

A request consists of

• the unique ID of the server
• the request ID (unique per server)
• the request command
• the arguments

replies

A reply consists of

• the request ID
• the reply status (success, error, ...; depends on request command)
• the arguments