Toma is a Topic Map Query Language, Topic Map Manipulation Language and Topic Map Constraint Language. Although its syntax is similar to that of SQL, it has a powerful path expression syntax which allows to access elements of the topic map. Toma offers the SELECT, INSERT, UPDATE and DELETE statements, used to query and manipulate the topic map. The MERGE statement is used to merge topic maps, and the EXPORT statement is used to export the topic map to XTM. Set of statements are provided for defining and managing constraints. Finally, Toma provides functions which allow to modify, convert and aggregate the data coming from the topic map.