How do you design a database schema for a user profile page

Question

Trying to set up a user profile page for a job site. The database I plan to use is the MySQL database.

Looking into a few database design I came up with this schema.

First, the user management tables

CREATE TABLE `user` (
  `user_id` int(11) NOT NULL,
  `firstname` varchar(32) NOT NULL,
  `lastname` varchar(32) NOT NULL,
  `email` varchar(96) NOT NULL,
  `mobile_number` varchar(32) NOT NULL,
  `password` varchar(40) NOT NULL,
  `salt` varchar(9) NOT NULL,
  `address_id` int(11) NOT NULL DEFAULT '0',
  `ip` varchar(40) NOT NULL,
  `status` tinyint(1) NOT NULL,
  `approved` tinyint(1) NOT NULL,
  `registration_date` datetime NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8;

CREATE TABLE `user_address` (
  `user_id` int(11) NOT NULL,
  `city` varchar(128) NOT NULL
  `work_city` varchar(128) NOT NULL,
  `postal_code` varchar(10) NOT NULL,
  `country_id` int(11) NOT NULL DEFAULT '0'
) ENGINE=MyISAM DEFAULT CHARSET=utf8;

CREATE TABLE `user_description` (
  `user_id` int(11) NOT NULL,
  `description` text NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=utf8;

and then the education table and work experience

CREATE TABLE `education_detail` (
  `user_id` int(11) NOT NULL,
  `certificate_degree_name` varchar(255) DEFAULT NULL,
  `major` varchar(255) DEFAULT NULL,
  `institute_university_name` varchar(255) DEFAULT NULL,
  `start_date` date NOT NULL DEFAULT '0000-00-00',
  `completion_date` date NOT NULL DEFAULT '0000-00-00'
)

CREATE TABLE `experience_detail` (
  `user_id` int(11) NOT NULL,
  `is_current_job` int(2) DEFAULT NULL,
  `start_date` date NOT NULL DEFAULT '0000-00-00',
  `end_date` date NOT NULL DEFAULT '0000-00-00',
  `job_title` varchar(255) DEFAULT NULL,
  `company_name` varchar(255) DEFAULT NULL,
  `job_location_city` varchar(255) DEFAULT NULL,
  `job_location_state` varchar(255) DEFAULT NULL,
  `job_location_country` varchar(255) DEFAULT NULL,
  `job_description` varchar(255) DEFAULT NULL
)

Note that user_id in table user_address, user_description, education_detail and experience_detail is a foreign key referencing it to the table user.

There are a few more table like skills, certification etc to which I plan on using user_id as a FK.

My question, is this database design good enough? Can you suggest me what should be done more to make the design much better?

Keep in mind not all will have work experience, some may be freshers.

Answer 1

Use InnoDB, not MyISAM. (There are many Q&A explaining 'why'.)

NULL or an empty string is perfectly fine for a missing description . Do you have any further argument for disliking such? (Meanwhile, InnoDB is more efficient at handling optional big strings.)

Every table should have a PRIMARY KEY ; you don't seem to have any. The first table probably needs user_id as the PK. Read about AUTO_INCREMENT .

As with description , why is address in a separate table?

May I suggest this for country name/code/id:

country_code CHAR(2) CHARACTER SET ascii

Education is 1:many from users, so user_id cannot be the PK. Ditto for jobs.