Fetching data from three tables? - mysql

Question

I have three tables category, brand, product.
Category table -
+---------------+--------------+------+-----+---------+----------------+
| id | int | NO | PRI | NULL | auto_increment |
| category_name | varchar(255) | NO | | NULL | |
| category_UID | varchar(255) | NO | UNI | NULL | |
| date | date | YES | | NULL | |
| time | time | YES | | NULL | |
| is_delete | tinyint(1) | YES | | 0 | |
+---------------+--------------+------+-----+---------+----------------+
Brand table -
+------------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+------------+--------------+------+-----+---------+----------------+
| id | int | NO | PRI | NULL | auto_increment |
| brand_name | varchar(255) | NO | | NULL | |
| brand_UID | varchar(255) | NO | UNI | NULL | |
| fk_id | varchar(255) | NO | | NULL | |
| date | date | NO | | NULL | |
| time | time | NO | | NULL | |
| is_delete | tinyint(1) | YES | | 0 | |
+------------+--------------+------+-----+---------+----------------+
Products -
+-----------------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------------+--------------+------+-----+---------+----------------+
| id | int | NO | PRI | NULL | auto_increment |
| category_UID | varchar(255) | NO | | NULL | |
| brand_UID | varchar(255) | NO | | NULL | |
| product_name | varchar(255) | NO | | NULL | |
| product_UID | varchar(255) | NO | UNI | NULL | |
| keyword | varchar(255) | YES | | NULL | |
| photo | varchar(255) | NO | | NULL | |
| photo_thumbnail | varchar(255) | YES | | NULL | |
| date | date | NO | | NULL | |
| time | time | NO | | NULL | |
| is_delete | tinyint(1) | YES | | 0 | |
| visible | tinyint(1) | YES | | 1 | |
+-----------------+--------------+------+-----+---------+----------------+
In HTML page there is a search type input in which user will type atleast three characters to get the serach result from DB.
How will be search technique -
I want to search for products and grab all their data.
The search string will be find by product_name or keywords from product table.
If the search string doesn't found in product table then the search string may be find by category_name or brand_name from category table or brand table respectively. Now If we get our search then the category_UID must be present in product table. (It means we will get our search only when that category UID stored in product table)
I want to get the output as -
If search success, we must get all the column data from product table including two more columns category_name, brand_name from category table and brand table respectively.
Note :
only one attribute category_UID is common in all three tables.
So How can I get the search for product ?
Is this can be solved by JOIN or UNION technique else I have to use procedural way.

Answer 1

In your table, category_UID and product_UID are the foreign keys references, then the following query will work.
select p.id as id,p.category_UID as category_UID,p.brand_UID as brand_UID,
p.product_name as product_name,p.product_UID as product_UID,p.keyword as keyword,
p.photo as photo,p.photo_thumbnail as photo_thumbnail,p.date as date,p.time as time,
p.is_delete as is_delete,p.visible as visible,c.category_name as category_name, b.brand_name as brand_name
FROM product as p
JOIN Brand as b ON p.brand_UID = b.brand_UID
JOIN category as c ON p.category_UID = c.category_UID
where p.product_name like '%<search_str>%' OR
p.keyword like '%<search_str>%' OR
b.brand_name like '%<search_str>%' OR
c.category_name like '%<search_str>%';