com.bigdata.rdf.sparql.ast

Interface ASTBase.Annotations

All Superinterfaces:

BOp.Annotations

All Known Subinterfaces:

ASTContainer.Annotations, BindingsClause.Annotations, QuadsDataOrNamedSolutionSet.Annotations, QueryBase.Annotations, QueryNodeBase.Annotations, QueryRoot.Annotations, RangeNode.Annotations, SliceNode.Annotations, UpdateRoot.Annotations, com.bigdata.rdf.sparql.ast.ValueExpressionNode.Annotations, VarNode.Annotations

Enclosing class:

ASTBase

public static interface ASTBase.Annotations
extends BOp.Annotations

Field Summary

Fields

Modifier and Type	Field and Description
static String	EXPLAIN_HINTS An optional ExplainHints object specifying hints to be exposed to the user when requesting an explanation of the query.
static String	QUERY_HINTS An optional Properties object specifying query hints which apply to this AST node.

Fields inherited from interface com.bigdata.bop.BOp.Annotations

BOP_ID, CONTROLLER, DEFAULT_CONTROLLER, DEFAULT_EVALUATION_CONTEXT, DEFAULT_TIMEOUT, EVALUATION_CONTEXT, NAMESPACE, TIMEOUT

Field Detail

QUERY_HINTS

static final String QUERY_HINTS

An optional Properties object specifying query hints which apply to this AST node.

The relationship between SPARQL level query hints, the annotations on the ASTBase and PipelineOp nodes is a bit complex, and this Properties object is a bit complex. Briefly, this Properties object contains property values which will be applied (copied) onto generated PipelineOps while annotations on the ASTBase nodes are interpreted by IASTOptimizer s and AST2BOpUtility. SPARQL level query hints map into one or another of these things, or may directly set attributes on the AST2BOpContext.

See Also:

ASTQueryHintOptimizer, Clean up query hints , Constant Field Values

EXPLAIN_HINTS

static final String EXPLAIN_HINTS

An optional ExplainHints object specifying hints to be exposed to the user when requesting an explanation of the query.

See Also:

Constant Field Values