In this article we discuss how schemaless docs can be used in Percolate Queries.

The Percolate Query feature allows storing not only fulltext matches, but also regular attribute filtering.
Until 2.7.0 this was limited to a single numeric attribute condition.

Now filtering can work with string and JSON attributes. The JSON filtering is interesting as you can test schemaless documents against stored queries. The filtering also now supports multiple attribute filtering and usage of expressions, which allows more complex stored criterias.
[…]

mysql> CALL PQ ('pq', ('{"title":"butter is good as", "id":3}', 
                       '{"title":"was butter","id":4}', 
                       '{"title":"sas was butter","id":5}', 
                       '{"title":"bas was butter", "id":6}', 
                       '{"title":"butter is good as","id":7}'), 
                 1 as docs_json ,1 as docs,1 as query);
+------+-----------+------------+------+---------+
| UID  | Documents | Query      | Tags | Filters |
+------+-----------+------------+------+---------+
|    1 | 1,5       | butter is  |      |         |
|    2 | 2,3,4     | butter was |      |         |
+------+-----------+------------+------+---------+
2 rows in set (0.00 sec)