DB Structure : Ok or not? - mysql

Question

I am developing an application management business (sales, suppliers, customers, products, ...) for a new company. To begin, I need to create a database. Could you please tell me if the BD scheme bellow is good and optimized ?
CREATE TABLE IF NOT EXISTS `company` (
id UNSIGNED INT NOT NULL auto_increment,
`SIRET` varchar(50) NOT NULL,
`nom` varchar(50) NOT NULL,
`description` varchar(500) NOT NULL,
`enable` ENUM('YES', 'NO') DEFAULT 'YES',
`level` int(1) NOT NULL,
PRIMARY KEY (id),
UNIQUE KEY SIRET (SIRET)
) ENGINE=INNODB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
// contactType can be one of the 3 values : email, phone, fax
CREATE TABLE IF NOT EXISTS `contactType` (
id UNSIGNED INT NOT NULL auto_increment,
`contactType` ENUM('email', 'phonenumber', 'faxnumber')
`mobile` ENUM('YES', 'NO') default 'NO',
PRIMARY KEY (id),
UNIQUE KEY type (contactType)
) ENGINE=INNODB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
CREATE TABLE IF NOT EXISTS `contacts` (
id UNSIGNED INT NOT NULL auto_increment,
`SIRET` varchar(50) NOT NULL,
`contactType` varchar(50) NOT NULL, // A reference to contactType just above
`contactref` varchar(50) NOT NULL, // Phone number, fax number or email adress
PRIMARY KEY (id),
UNIQUE KEY type (SIRET)
) ENGINE=INNODB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
CREATE TABLE IF NOT EXISTS `customers` (
id UNSIGNED INT NOT NULL auto_increment,
`SIRET` varchar(50) NOT NULL,
PRIMARY KEY (id),
UNIQUE KEY type (SIRET)
) ENGINE=INNODB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
CREATE TABLE IF NOT EXISTS `supplier` (
id UNSIGNED INT NOT NULL auto_increment,
`SIRET` varchar(50) NOT NULL,
PRIMARY KEY (id),
UNIQUE KEY type (SIRET)
) ENGINE=INNODB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
CREATE TABLE IF NOT EXISTS `industry` (
id UNSIGNED INT NOT NULL auto_increment,
`industry` varchar(250) NOT NULL,
PRIMARY KEY (id),
UNIQUE KEY type (activite)
) ENGINE=INNODB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;
CREATE TABLE IF NOT EXISTS `entreprisePerIndustry` (
id UNSIGNED INT NOT NULL auto_increment,
`industry_id` varchar(250) NOT NULL, // Chemical, Computer, Consulting, ...
FOREIGN KEY (industry_id) REFERENCES industry(id) ON DELETE CASCADE,
`SIRET` varchar(50) NOT NULL,
PRIMARY KEY (id),
UNIQUE KEY type (industry_id)
) ENGINE=INNODB DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;

Answer 1

Below are few TIPS which can helps you to create better DB
Change table engine from MyISAM to InnoDB if you want make foreign key constrains to work.
AUTO INCREMENT DataType should be UNSIGNED INT. this will double the range.
`id` INT UNSIGNED NOT NULL AUTO_INCREMENT`
if a column value chosen from a list of permitted values then change dataType to ENUM .In your case enable, level can be turned into ENUM dataType
`enable` ENUM( 'y', 'n' ) NOT NULL DEFAULT 'y' COMMENT 'y:yes; n:no' `
add foreign key relation to
contacts.contactType with contactType.id
entreprisePerIndustry .industry with industry.id
update
I have created basic and optimized table structure ( AFAIK ).
--
-- Table structure for table `tbl_company`
--
CREATE TABLE IF NOT EXISTS `tbl_company` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`siret` varchar(50) NOT NULL,
`nom` int(11) NOT NULL,
`description` varchar(250) NOT NULL,
`enable` enum('y','n') NOT NULL DEFAULT 'y' COMMENT 'y:yes; n:no',
`level` enum('1','2') NOT NULL DEFAULT '1',
`last_updated_on` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;
--
-- Table structure for table `tbl_contact`
--
CREATE TABLE IF NOT EXISTS `tbl_contact` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`siret` varchar(50) NOT NULL,
`contact_type` enum('email','phone','fax') NOT NULL DEFAULT 'email',
`contact_ref` varchar(100) NOT NULL COMMENT 'Phone number, fax number or email adress',
`last_updated_on` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`id`),
UNIQUE KEY `siret` (`siret`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=1 ;
...
...
complate structure is here