A DAH has three child servers:
server 0 has a database of dog information, called dogs
.
server 1 has:
cats
.parrots
.server 2 has a database of flower information, called flowers
.
The following DAH VDB configuration queries all information about pets:
[VDB0] Name=pets MapsTo=0:dogs,1:cats,1:parrots Type=combinator
In this example, note that:
You do not have to reference all child servers in the MapsTo
parameter.
You can reference the same child server multiple times.
When DAH receives a query with DatabaseMatch
set to pets
, DAH sends:
the query with DatabaseMatch
set to dogs
to server 0.
the query with DatabaseMatch
set to cats+parrots
to server 1.
There are other advanced distribution options for VDBs, such as multi-stage querying. For more information, refer to the DAH Reference.
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