The tokens table corresponding to the utterance in Figure 1 as it would appear in the relational database. Each row corresponds to a single token. The Level column refers to a table of level names, the Seq column contains the sequence number of each token within its level. Any commercial relational database system could be used in it's place with minor modifications to the translation scripts. The Emu system supports a special purpose query language designed to make the most common queries easy to express while allowing the experienced user to take full advantage of complex hierarchical structure.
More complex queries can refer to sequential and hierarchical relations within the annotation.
The Emu query syntax has a few other constructs but this subset is sufficient for the purposes of this paper. The result of an Emu query is a table with one row per matching token and columns for the token label, start time, end time and utterance name. This table can be used to extract the corresponding speech data for each token. A query specifies constraints on rows of the tables to be returned and the names of the columns to be included in the returned table. Columns may be taken from more than one table to construct the result.