We have been using  PostgresSQL  in our new product Quiz Stack. Quiz Stack is a SAAS based  product. Which can  conduct,manage,analysis quizzes.We are using rails and postgresql as our backend.It’s subdomain app and hence we decide to use postgresql schema based approach for storing/querying data. While working on one of the feature It was needed to draw some random fixed questions for each user.So each user has different order of questions which  is maintain for each specific user. In Mysql it’s …