Improve query performance when finding graphs containing a subject

(In [2201]) re #310 reviewer: lee

Add Glitter.widenBindableIsolationScope and call from Glitter.isNeededOutsideOfNode. Optimize ldap solution generator list attributes of entries only when they are actually needed.

Lee,

Would you review and close? Thanks!

-Joe

(In [2207]) re #310 reviewer: lee

Reduce use of isNeededOutside in favor of isUsedOutside due to bugs in the wild.

(In [2211]) re #310 reviewer: lee

re-activate use of isNeededOutsideNode that was reduced in r2207. The actual issue was #313, not the isNeededOutsideNode method.

Joe, I think that the filter check in isNeededOutsideOfNode(...) might need to be done on the original node rather than the widened node. Consider the pathological case of:

{ ... } 
  UNION 
{  -- n2
  { 
    ?s :foo :bar .  -- n1
  }
  FILTER(?s = :qux) .
}

In this case, the original node will be n1 and the widened node will be, n2. The filter is in scope for n1 but out of scope for n2. Yet we need the variable outside of n1 to properly evaluate the filter.

Two possible fixes:

• do the filter check against the original (unwidened) node
• check explicitly for filters in while walking up the tree in widenBindableIsolationScope()

Everything else looks good. Feel free to fix or refute and close.

Oops, those are SQL comments, not SPARQL comments :-)

(In [2231]) re #324, #310 reviewer: lee

Don't widen binding isolation scope if a filter is in the chain (re #310) Support textmatch in ldap and relational solution generators (re #324) Introduce 'context' classes to reduce param counts throughout ldap and relational bridge code. Move ldap mapper classes to anzo-server. Modernize naming:

• 'querybuilder' becomes bridge.relational, to match sibling bridge.ldap
• 'RdbGraph?' becomes 'RdbTriplePatternSolver?'

Responded to review in comment 7, thanks for noticing this situation Lee. Marking as fixed.