> On Mar 24, 2024, at 5:08 PM, Andy Seaborne <[email protected]> wrote: > > > > On 21/03/2024 00:21, Jim Balhoff wrote: >> Hi Lorenz, >> These both do speed things up quite a bit, but it prevents matching patterns >> that cross graphs in the case where I include multiple graphs. >> Thanks, >> Jim > > It is the combination choosing certain graphs and wanting cross graph > patterns that pushes the code into working in general way. it works in Nodes, > and that means string comparisons. That looses the TDB ability to do faster > joins using NodeIds which both avoids string comparisons and retrieving the > strings until they are known to be needed for the results.
Thanks, this explanation makes sense. > > Is there a reason for not having a union default graph overall the named > graphs instead of selecting certain ones? If it is all named graphs, the > union is TDB2 level. For certain use cases, we would like include and exclude graphs depending on the query. Also, we are typically running off of HDT rather than TDB2. > > You can have a Fuseki setup with two endpoints - one that does union default > graph, one that does not, for the same dataset.
