The entity DIRECTORS represents the set of directors. The entity MOVIES represents the set of movies. A sub property of description. The entity relationship schema contains three entities, MOVIES, ACTORS and DIRECTORS, and two relationships, CASTING and ISDIRECTEDBY. tools may have only weaker understanding of extra types, in particular those defined externally. Let us consider a database on movies and informations about (actors, directors and so on). Information from other properties (in particular, name) may be necessary for the description to be useful for disambiguation. e.g. The cardinality 1,1 between MOVIES and DIRECTORS may be read as "a movie is directed by one and only one director". Is is a many-to-many relationships between MOVIES and ACTORS. See. “NoSQL databases” is really used to denote a varied set of database modeling paradigms that are grouped usuallyin four main types: document, wide column, key-value stores and graph-based databases. the URL of the item's Wikipedia page, Wikidata entry, or official website. Property Expected Type Description; Properties from Movie; actor: Person : An actor, e.g. The cardinality 1,n between ACTORS and CASTINGS may be read as "an actor may have played in 1 to n movies". The cardinality 1,n between MOVIES and ACTORS can be read as " a movie may have from 1 to n actors playing in". The ord attribute precise the rank of the actor in the movie. Example/instance/realization/derivation of the concept of this creative work. A work that is a translation of the content of this work. Short table structure descriptions are given below: The movie table contains data about movies which will be shown in the theater. The relational schema of this database is described as follow : MOVIES (id, title, yr, score, votes, director) ACTORS (id, name) CASTINGS (movieid, actorid, ord) DIRECTORS(id, name) An actor may play a role in zero to several movies and in a movie we have one to several actors who play in. Assume that MOVIES is a populated database. The entity ACTORS represents the set of actors. The cardinality 1,n between DIRECTORS and MOVIES may be read as "a director may have directed 1 to n movies". The entity DIRECTORS is translated to a relation DIRECTORS, with key "id" and attribute "name". eg. However, … The relationship CASTINGS is translated to a relation CASTINGS with the attributes "actorid", "movieid" and "ord". A short description of the item used to disambiguate from other, similar items. actorid is a foreign key on ACTORS and movie id is a foreign key on MOVIES. The couple (actorid, movieid) is a key for the table. There’s a lot of confusion about schemas when it comes to databases. 1 Relational schema. The identifier property represents any kind of identifier for any kind of, Indicates a page (or other CreativeWork) for which this thing is the main entity being described. The key attribute is "id". In RDFa syntax, it is better to use the native RDFa syntax - the 'typeof' attribute - for multiple types. (IMDb pre-dates the web by several years.) The notion of schema is well-defined for relational databases. The relational schema of this database is described as follow : An actor is described by an identifier (integer, key of the table) and a name. The version of the CreativeWork embodied by a specified resource. The key attribute is "id". The key of the relation CASTINGS is the couple . The question often arises whether there’s a difference between schemas and databases and if so, what is the difference. The paperback edition, first edition, or eBook. This is a relationship between something and a class that the thing is in. The entity MOVIES is translated to a relation MOVIES, with the key "id" and with the attributes "title", "yr", "score", "votes" and "director". Indicates a potential Action, which describes an idealized action in which this thing would play an 'object' role. Given the constraints shown in the ER schema, respond to the following statements with True, False, or Maybe. More details on this classification can be found in . This database is inspired from the movie database. The typical expected age range, e.g. Organization or person who adapts a creative work to different languages, regional differences and technical requirements of a target market, or that translates during some event. IMDb started out as a flat-file database coupled with some Perl scripts that were shipped around on usenet. A director is identified by an id (integer, key of the table) and a name. references). Use PDF export for high quality prints and SVG export for large sharp images or embed your diagrams … The relationship ISDIRECTEDBY is translated by the inclusion of a foreign key (director) to DIRECTORS into the MOVIE table. © Computer Science Department - INT Evry. URL of a reference Web page that unambiguously indicates the item's identity. "movieid" references a movie in the relation MOVIES. A CreativeWork or Event about this Thing. It is a one-to-one relationship beteween MOVIES and DIRECTORS. Let us consider a database on movies and informations about (actors, directors and so on). The relationship "CASTINGS" represents the set of actors' participations on movies. ACTOR is used as a generic term and includes actresses. 西遊記 has an English workTranslation “Journey to the West”,a German workTranslation “Monkeys Pilgerfahrt” and a Vietnamese translation Tây du ký bình khảo.