Question

I was wondering how to handle money in a SQL database to maintain consistency. I presume the tables would look something like below.

Consider the following scenario: if two players are playing then the money they wagered has been deducted from both of their balance_usd and added to pot_usd. But suppose the server goes down in the middle of the hand. Consistency of the database here presumably would mean that the money in pot_usd should be returned to the two players balance_usd effectively canceling the hand. It doesn’t seem that transactions alone can solve this problem. How should the backend of a poker server be architected to handle this?

table user
    user_id
    balance_usd

table game
    game_id
    pot_usd
    ...

Answer 1

To cope with that eventuality, you could have a table of CurrentGameStakes with fields for the playerID and the amount staked. Then when the hand is finished, you transfer the total of the stakes to the winner, and if a game doesn’t complete for some reason, you return the staked amount to each player.