Related tags with Tags.app and Movable type

I’m using Tim Appnel’s excellent Tags.app to create my tags pages. For example, see my bestof tag that highlights some of my favorite blog entries.

A new addition to my tag pages is a list of tags that are regularly used with the selected tag. For example, when I use the tag folksonomy I often use the tags tags, tagyu, tagging, simplelinks, web20 — those terms are related to folksonomy because I commonly use them together.

To install this feature on your site, you’ll first need to be using the Tags.app plugin. You’ll also need to have Brad Choate’s SQL plugin. And you’ll need to be using MySQL as your database. This might work with other SQL databases, but I haven’t tested it, so you’re on your own there.

Stick this code somewhere in your tag page templates…

Related tags: <MTSQL query="SELECT t1.tagmap_tag, count(t1.tagmap_tag) AS cnt FROM mt_tagmap as t1, mt_tagmap as t2 WHERE t2.tagmap_tag='[MTSearchString]' and t2.tagmap_entry_id=t1.tagmap_entry_id and t1.tagmap_tag != '[MTSearchString]' GROUP BY t1.tagmap_tag ORDER BY cnt desc LIMIT 5"><a href="/tag/<MTSQLColumn column="1">"><MTSQLColumn column="1"></a> </MTSQL>

The entire thing needs to be on a single line in your MT template.

This will take the top 5 tags by usage that are used in entries where the current tag is also used. Want to show more or less tags? Change the LIMIT 5 to LIMIT 10 or whatever number you’d like.