mysql - #1005 - Can't create table 'xxx.item' (errno: 150) -

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i creating database hotel , not able create "item" table.

the error shown 

#1005 - can't create table 'xxx.item' (errno: 150)

below sql queries: 

create table menu (      menu_id int    , menu_name varchar(100)   , primary key (menu_id)  );   create table categories (      categories_id int    , category_name varchar(100)   , primary key (categories_id)  );   create table menu_category_item (      mci_id int    , menu_id int   , categories_id int    , item_id int    , item_type int   , restaurant_id int    , primary key (mci_id)   , foreign key (menu_id)        references menu(menu_id)   , foreign key (categories_id)        references categories(categories_id)   , foreign key (restaurant_id)        references restaurants(restaurant_id) );   create table item (     item_id int   , item_name varchar(100)   , item_price decimal   , foreign key (item_id)        references menu_category_item (item_id) );

please me out of this!!

i think problem in structure of database, should have item_id primary key in item table, let menu_category_item table reference that. like:

create table item (     item_id int   , item_name varchar(100)   , item_price decimal   , primary key (item_id));  create table menu_category_item (      mci_id int    , menu_id int   , categories_id int    , item_id int    , item_type int   , restaurant_id int    , primary key (mci_id)   , foreign key (menu_id)        references menu(menu_id)   , foreign key (categories_id)        references categories(categories_id)   , foreign key (restaurant_id)        references restaurants(restaurant_id)   , foreign key (item_id)        references item(item_id) );

if i'm correct, item table contain items, need primary key there. , menu_item_category matching items menus, there add foreign key.

comment @adam below:

as rule: 1 - every table should have primary key , 2 - foreign keys should against primary key target table. there exceptions, rules starting places basic db design imo


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