Equivalent URIs are conceptually stored in a bundle. A bundle is a set of URIs referring to resources which are considered to be equivalent, in a given context. A URI can exist in at most one bundle within a linked data set exposed by a sameAs Lite instance.
One URI in each bundle is nominated to be a canonical identifier, or canon, for that bundle. The canon represents a preferred URI for the set of duplicates.
An application that wishes to use data from multiple sources as if they were a single resource can process results by looking up URIs within sameAs Lite and replacing these with their canons on the fly. This reduces the multiplicity of identifiers to a single definitive URI.
For more information about the concepts underpinning sameAs Lite, see Glaser, H., Jaffri, A. and Millard, I. C. (2009) Managing Co-reference on the Semantic Web. In: Linked Data on the Web (LDOW2009), April 2009, Madrid, Spain.
sameAs Lite stores equivalent URIs within a single database table which associates an URI with its canon. The schema of this table is as follows:
For MySQL:
+--------+--------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------+--------------+------+-----+---------+-------+
| canon | varchar(256) | YES | MUL | NULL | |
| symbol | varchar(256) | NO | PRI | | |
+--------+--------------+------+-----+---------+-------+
For SQLite:
+--------+------+-----+
| Field | Type | Key |
+--------+------+-----+
| canon | TEXT | |
| symbol | TEXT | PRI |
+--------+---- -+-----+
A database index is created on canon.