newbie E-R question

[Anon]

Hello, i have built a db site with php/mysql and at the moment i am storing all of the following in one table ( catagory, subcategory, name, description, image name, price, id# (auto increment) )...my question is, should (since at the moment i am using SELECT DISTINCT category) put the category, subcategory and #id in one table and then id# and the rest in another to make it easier?? and how is this done when refering to a object that has a category and subcategory then id# ??? not sure how....thanks for any help here

[tomhath]

It depends on whether you are maintaining any other information about the categories and subcategories. If so, it would make sense to make them separate tables (read about database normalization).

Normally each table has a Primary Key that gets you to a single row in the table. Fastest and easiest way to implement a Primary Key is with an autoincrementing id column. Put that id in the other tables to connect them (read about Foreign Keys and Indexes). Linking the tables is easy if you know about php's mysql_insert_id function.

How about something like this:

Table Categories
id auto incremented int
Name

Description

Table Subcategories
id auto incremented int
Name

Description

CategoryId int

Table Images
id autoincrement int
Name

Description

Price
CategoryId int
SubcategoryId int

[Anon]

thanks for your reply...so i need to have three tables? The subcategories are obviously subcategories of the categories, do they need to be in seperate tables with additional fields other than just the id# ? cant i just leave out the other fields and put all the info such as name, description price, image etc in another table??