Question

Am trying to build a conversation system for users on a web app am working on.
At the the moment am quite confused on how to setup the database tables.
for now i have a table with fields this

• C_id

• Message

• S_id
• R_id
• read
• date_time

Answer 1

Assuming your table is a conversation table (C_id), I would have three tables in all:

1. Conversation
2. Message
3. User

You look to have the third, but have collapsed the other two together. The relevant fields would be:

User
   U_id (PK)
Conversation
   C_id (PK)
   R_id (FK on U_id)
   S_id (FK on U_id)
   fields relating to the conversation only - eg  the date-time it started.
Message
   M_id (PK)
   Text
   Date_time
   Has_been_read
   Author_id (FK on U_id)
   Conversation_id (FK on C_id)