Advanced search in the BIOP

Period limits the search to a century or a range of dates; technique and materials specify the nature of the object (oil on canvas, bronze, terracotta, polychrome wood). Dimensions are expressed with a ten per cent tolerance, since measurements vary from one recording to another.

Country and date of disappearance are used to link a work to a known case. The record status makes it possible to display only active alerts, or conversely works that have been found, useful for studying the history.

The operators AND, OR and EXCEPT are used between terms. For example "bronze AND dancer EXCEPT Degas" displays records of bronzes of dancers excluding one artist. Quotation marks search for an exact phrase.

Criteria can be combined or loosened. If the search returns too few results, remove the most restrictive criterion; if it returns too many, add the period or the dimensions.

An advanced query can be saved under a name (for example "19th-century sculptures Europe"). It can then become an alert: you are warned as soon as a new record matches it. An operator can save up to twelve queries.

Export of results (CSV or PDF) is reserved for professional accounts. It includes the fields useful for due diligence: record identifier, date of consultation, criteria used.

The advanced search engine is revised each year with the help of users. The latest version added search by distinctive mark (signature, hallmark, stamp) and by type of damage, useful for recognising a restored work.

Work is under way on free-text search in natural language, which would make it possible to enter a sentence such as "wooden statuette with one arm raised"; it requires precise control of the quality of results.