15. A database access component comprising: a communications interface arranged to receive an identifier of a database, the identifier comprising at least an address of the database; an inference engine arranged to receive at least one of: database column types; or an indication of whether the database columns are input, latent, or observable; a processor arranged to annotate a schema of the database with a plurality of expressions which describe probability distributions over entries in the database; a communications interface arranged to use the annotated schema to access the database and to obtain, as the result of inference on the accessed data according to the annotated schema, one or more predictive probability distributions over entries of the cells.
17. A database access component as claimed in claim 15 arranged to modify the database by adding columns and or tables according to the annotated schema and arranged to write entries to the added columns and or tables according to the one or more predictive probability distributions.