PHP MySQL查询单个查询中的多个类别

Question

I have an application that categorizes links for a tools page. On this page I want to have multiple categories and each tool under those categories. As I am going to have 13 categories (with more as the tool gets used) I don't want to run a query for each category. I would prefer to run a single query to grab all the data.

Right now I have the page setup so that it displays each category with a drop down to view the tools. What I need to do is have it so that only the tools for that category show up. I'm having a problem working out how to go through all of that data from a single query.

Currently I am using a while statement to run through the results as an array.

while($tools = $result->fetch_assoc()){
    if($tools['id'] = 1){
        echo $tools['name'];
    }
}

This is just a basic mockup of what I currently plan on doing. I can't help thinking however there is a better way to go about this. What is the best way to grab a big chunk of data from MySQL and then break it out into categories with PHP? If I need to run more than a single query that is fine, but I prefer not running a query for each category.

Answer 1

If you don't have performance problems you can use GROUP_CONCAT function like this,

SELECT id,GROUP_CONCAT(name)
FROM tools
GROUP BY id

you may read more abut GROUP_CONCAT from mysql official web site here