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KGConf / BookClub-Designing-BuildingEnterpriseKG

This is the Github Repository for the Knowledge Graph Conference Book Club around the book " Designing and Building Enterprise Knowledge Graphs: Synthesis Lectures on Data, Semantics, and Knowledge" with Juan Sequeda and Ora Lassila
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Could you specify "_if it is not the last column in the primary key, the “;” character._"? #4

Closed msesboue closed 2 years ago

msesboue commented 2 years ago

Chap 2, page 34, section 2.3.1, paragraph Direct Mappings to RDF Graphs, I fail to understand what "the last column in the primary key" refers to. Could you give an example?

dwinston commented 2 years ago

For a table Person with columns (first_name, last_name, birth_date, description), it's possible that the primary key may be a compound key, e.g. (first_name, last_name, birth_date) to uniquely identify a row (if there is no "ID" column). So in this case, the "last column" would be birth_date.

msesboue commented 2 years ago

Thank you It makes sense now :)