DB Schema For Chats? - mysql

Question

I need to store chat conversations in a database schema. The way I would use this database is I would post chats on a website. Each chat would not be more than about 20 responses. Can someone please suggest a schema for this?

Answer 1

Here's a start using MySQL Workbench
and the create script
SET #OLD_UNIQUE_CHECKS=##UNIQUE_CHECKS, UNIQUE_CHECKS=0;
SET #OLD_FOREIGN_KEY_CHECKS=##FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0;
SET #OLD_SQL_MODE=##SQL_MODE, SQL_MODE='TRADITIONAL';
CREATE SCHEMA IF NOT EXISTS `chats` DEFAULT CHARACTER SET utf8 COLLATE default collation ;
-- -----------------------------------------------------
-- Table `chats`.`chat`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `chats`.`chat` (
`id` INT UNSIGNED NOT NULL AUTO_INCREMENT ,
PRIMARY KEY (`id`) )
ENGINE = InnoDB;
-- -----------------------------------------------------
-- Table `chats`.`chat_user`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `chats`.`chat_user` (
`id` INT UNSIGNED NOT NULL AUTO_INCREMENT ,
`handle` VARCHAR(45) NOT NULL ,
PRIMARY KEY (`id`) )
ENGINE = InnoDB;
-- -----------------------------------------------------
-- Table `chats`.`chat_line`
-- -----------------------------------------------------
CREATE TABLE IF NOT EXISTS `chats`.`chat_line` (
`id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT ,
`chat_id` INT UNSIGNED NOT NULL ,
`user_id` INT UNSIGNED NOT NULL ,
`line_text` TEXT NOT NULL ,
`created_at` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ,
PRIMARY KEY (`id`) ,
INDEX `fk_chat_line_chat` (`chat_id` ASC) ,
INDEX `fk_chat_line_chat_user1` (`user_id` ASC) ,
CONSTRAINT `fk_chat_line_chat`
FOREIGN KEY (`chat_id` )
REFERENCES `chats`.`chat` (`id` )
ON DELETE NO ACTION
ON UPDATE NO ACTION,
CONSTRAINT `fk_chat_line_chat_user1`
FOREIGN KEY (`user_id` )
REFERENCES `chats`.`chat_user` (`id` )
ON DELETE NO ACTION
ON UPDATE NO ACTION)
ENGINE = InnoDB;
SET SQL_MODE=#OLD_SQL_MODE;
SET FOREIGN_KEY_CHECKS=#OLD_FOREIGN_KEY_CHECKS;
SET UNIQUE_CHECKS=#OLD_UNIQUE_CHECKS;
And you are welcome to download the MWB file from my dropbox.

Answer 2

Conversation has_may Lines
Line belongs_to User, has content & time