Querying muliple columns in MySQL table (PHP) - php

Question

I have a table with columns named: "ID, Track Name, City, County" among others. I'm looking for a way for a user to query the database and get results back relating to those 4 columns, with the most relevant results appearing at the top.
Say there was a row with: "1, Track Number One, Taunton, Somerset"
and a row with: "2, Circuit Number Two, Taunton, Somerset"
and the user searched "circuit in taunton"
Obviously I would like both rows to show, but I would like the second row to appear at the top because it has matched 2 keywords.
This is the current code I am using but it is only working on one column or another and if the user queried "karting in taunton" it would not work.
$searchterm = htmlspecialchars($getArray['searchterm']);
$searchterm = $mysqli->real_escape_string($searchterm);
$terms = explode(' ', $searchterm);
$bits = array();
$cityBits = array();
$countyBits = array();
foreach ($terms as $term) {
$bits[] = "name LIKE '%".mysql_real_escape_string($term)."%'";
}
foreach ($terms as $cityTerms) {
$cityBits[] = "city LIKE '%".mysql_real_escape_string($cityTerms)."%'";
}
foreach ($terms as $countyTerms) {
$countyBits[] = "county LIKE '%".mysql_real_escape_string($countyTerms)."%'";
}
$this->query = "SELECT * FROM tracks WHERE (".implode(' AND ', $bits).")
union SELECT * FROM tracks WHERE (".implode(' AND ', $cityBits).")
union SELECT * FROM tracks WHERE (".implode(' AND ', $countyBits).")";
I know this code is not ideal but it all I've managed to get working at the moment.

Answer 1

Firstly, your requirement is a much better match for full text searching than "like" comparisons. As soon as you get this working, you'll want to boost "Taunton" over "Aunton" and then deal with different spellings, wildcards, and then you'll notice that the wildcards in your like statement slow the whole thing down. Full text searching does all that for you, and is pretty quick.
The specific answer to your question is a nasty one; I'm reluctant to give you code PHP code because I can't easily test it. I've created a little SQLFiddle to show how you can do it in SQL, though.
In essence, you need to turn your "hits" on individual searches into a derived table, and count each row's number of entries; the more times it turns up in your derived table, the more likely it is to be a "good" hit.

Answer 2

In one of the places i've been working at, i had to do a search engine to search songs into a database (so basically what you're trying to do). The solution i came up with was : when you insert a song into the database, you also put some relevant keywords which should make the song appear when you type them.
So what's happening when someone search for let's say : MJ, my code was searching for exact matches into the artist name / song title. If i had results, i was displaying them by alphabetical number or by whatever the user wanted to sort them by.
If no results were found (and here's the interesting part for you) my function was doing a query into the keywords of each songs. Once i had all the results and especially their associated keywords into an array i was just counting the number of keywords matching the query for each result and only then i could sort by relevance.
Hope this helps you, i guess you're only missing a "keywords" row in your db.

Answer 3

Your query is setup to return 2 identical rows if 2 matches are found. You might reword it to return the row once, along with an ORDER BY clause that counts the matches.
"SELECT * FROM tracks WHERE (".implode(' AND ', $bits).")
OR (".implode(' AND ', $cityBits).")
OR (".implode(' AND ', $countyBits).")
ORDER BY ((".implode(' AND ', $bits).")
+ (".implode(' AND ', $cityBits).")
+ (".implode(' AND ', $countyBits).")) DESC"
This isn't exact, because I'm not sure why you are imploding with "AND" rather than "OR", but you get the jist.