Caractérisation des réponses certaines par compacité

As we have seen, leaving the case of provenance for aggregates, where-provenance, and recursive queries, to future work, provenance annotations can be Boolean functions (see Section

- A relational database is a collection of tables of data, each of which has one special column that stores the primary keys of the table.. - Rows are sometimes

As a result, we obtain an effective method for answering conjunctive queries that can handle imprecision described as rough approximations of a concept or as

We propose a two step bootstrapping architecture of integrating relational databases with the Semantic Web by first generating a “database- derived putative ontology” and

The classification of the relations, based on their keys and foreign keys, can be summarised as: base relation when the primary key is disjoint with every foreign key; specific

Even practi- cal algorithm to approximate certain answers (answers which are true regardless of how incomplete information is interpreted) are often de- veloped in the model with

Because it can be difficult to obtain exact descriptions of what stored procedures do, our framework abstracts data-transforming tools as black-box procedures, in which a

Since their computation is a coNP-hard problem, re- cent research has focused on developing evaluation algorithms with correctness guarantees, that is, techniques computing a sound