php - how can create categories with different options of it in mysql tables -

i want design database mysql categories options categories example : script classified .. when want add ads in "cars category" must add options car . when add ads in "apartments sale category" must add options apartment

or @ image dubizzle site classified

when want add car in "cars category" show options http://i.stack.imgur.com/gkgl8.png

and when want add ads in "apartments sale category" show options http://i.stack.imgur.com/dtnzi.png

how can design database such ??

categories , sub-categories different options categories 

create table category (     id int auto_increment primary key,     catname varchar(100) not null );  create table catoption (   -- no attempt share option across multiple categories     id int auto_increment primary key,     catid int not null,     descr varchar(100) not null,     listingorder int not null   -- order listed on screen      -- include fk category );  create table listing (     id int auto_increment primary key,     catid int not null,     title varchar(100) not null,     verbeage text,     price decimal(12,0) not null      -- include fk category );  create table listoptions (   -- table houses particular listing options (answers if will)     -- programmer chooses whether or not save 'blanks'     id int auto_increment primary key,     listingid int not null,     optionid int not null,     answer varchar(100) not null    -- choose datatype     -- include fk listing     -- include fk catoption ); 

the foreign key constraint used prevent actions destroy links between tables.

the foreign key constraint prevents invalid data being inserted foreign key column, because has 1 of values contained in table points to.