Data integration

Question

I consider Global data integration methods as view and Local as view, but I can’t find examples of how queries will be generated for them, can anyone give me examples of how these data integration methods can be requested using GAV and LAV , you are welcome,

I specifically ask about GAV and LAV here.

I know that GAV (global view) is described above data sources and that LAV (local as view) is described on top of an indirect scheme. However, I’m not quite sure what these terms mean and how they affect the generated query.

There is a wikipedia page for GAV, without an example request, and no wikipedia page for LAV is sad

Answer 1

I think that these terms are not widely used in industry - the only references that I see for them seem to arise from academic work. They apply to Enterprise Information Integration, a technology genre where the level of reporting or integration on the client side is placed on top of existing databases without storing data in a separate reporting database.

Essentially, Global As View describes where data is converted to a unified view before reporting. In a data warehouse (where data is converted and stored in a separate database) this view will be data warehouse tables. The EII tool can do this by issuing queries against underlying data sources and combining them into a centralized schema. However, EII is not a widely used technology.

"Local presentation methods" request all sources individually, and then combine the totality of the results. It is clear that this is the act of compiling several queries to various sources that create result sets in the same format, but the data source is from the place where it is located in the base systems. Data integration is then performed at the reporting level.