MySQL Cookbook

Performing Phrase Searches with a FULLTEXT Index

Problem

You want to perform a FULLTEXT search for a phrase, that is, for words that occur adjacent to each other and in a specific order.

Solution

Use the FULLTEXT phrase search capability, or combine a non-phrase FULLTEXT search with regular pattern matching.

Discussion

To find records that contain a particular phrase, you can’t use a simple FULLTEXT search:

mysql> SELECT COUNT(*) FROM kjv
    -> WHERE MATCH(vtext) AGAINST('still small voice');
+----------+
| COUNT(*) |
+----------+
|      548 |
+----------+

The query returns a result, but it’s not the result you’re looking for. A FULLTEXT search computes a relevance ranking based on the presence of each word individually, no matter where it occurs within the vtext column, and the ranking will be nonzero as long as any of the words are present. Consequently, this kind of query tends to find too many records.

As of MySQL 4.0.2, FULLTEXT searching supports phrase searching in Boolean mode. To use it, just place the phrase within double quotes.

mysql> SELECT COUNT(*) FROM kjv
    -> WHERE MATCH(vtext) AGAINST('"still small voice"' IN BOOLEAN MODE);
+----------+
| COUNT(*) |
+----------+
|        1 |
+----------+

Prior to 4.0.2, a workaround is necessary. You could use an IN BOOLEAN MODE search to require each word to be present, but that doesn’t really solve the problem, because the words can still occur in any order:

mysql> SELECT COUNT(*) FROM kjv
    -> WHERE MATCH(vtext)
    -> AGAINST('+still +small +voice' IN ...