Returning rows from database based on search query

I am having a product table with following schema:

products (itemname VARCHAR(50), itemid INT(10));

Sample records ar开发者_JS百科e shown below (itemname, itemid):

• blackberry curve 3g (black), 1
• samsung ace, 3
• blackberry curve 3g (white), 2
• apple iphone 4 32gb (black), 4

Now suppose user enters the query into the search box of the website and accordingly results are displayed. i.e. if user enters blackberry then Blackberry mobiles should be displayed

I am looking answers for the following questions:

1. How can search text be matched with the items? For example: user may enter blackberry in the search box then how it can be searched? Should I search for blackberry word as a sub-string of itemname column of the above table?
2. If the user enters two words like: apple 32gb. Now if I use the above mentioned method of sub-string then it wont work because there is no row in the table having apple 32gb as sub-string. How to search in this case?
3. If the user enters a very generic search text like: mobiles. In this case, all the mobile phones should be displayed. Matching the itemname as a sub-string will not work in this case also.
4. User may enter search text: apple 32gb black color. In this case, apple products of 32GB capacity and black color should be displayed.

I know that implementing the search 100% correct is not possible. I am just looking for hints/how to proceed. I am using PHP, MySQL, Apache.

What kind of database is this, if MySQL you can enabled fulltext search on the field and then just a simple query will get you the results you expect.

for many word searching I would do something like this:

$searchArray = explode(" ", $searchString);
foreach ($searchArray as $word)
{
    //add an OR clause to your sql query like the following
    $query .= "OR itemname like %".$word."%";
}

the other questions are far more complicated, but I hope this helps