Function QueryGraph_AddPath

src/graph/query_graph.c:278–314

}

void QueryGraph_AddPath
(
	QueryGraph *qg,                // query graph to add path to
	const cypher_astnode_t *path,  // path to add
	bool only_shortest             // interested only in the shortest paths
) {
	AST *ast = QueryCtx_GetAST();
	uint nelems = cypher_ast_pattern_path_nelements(path);
	// introduce nodes first
	// nodes are positioned at every even offset
	// into the path (0, 2, ...)
	for(uint i = 0; i < nelems; i += 2) {
		const cypher_astnode_t *ast_node =
			cypher_ast_pattern_path_get_element(path, i);
		_QueryGraphAddNode(qg, ast_node);
	}

	// every odd offset corresponds to an edge in a path
	for(uint i = 1; i < nelems; i += 2) {
		// retrieve the QGNode corresponding to the node left of this edge
		const cypher_astnode_t *l_node =
			cypher_ast_pattern_path_get_element(path, i - 1);
		const char *l_alias = AST_ToString(l_node);
		QGNode *left = QueryGraph_GetNodeByAlias(qg, l_alias);

		// retrieve the QGNode corresponding to the node right of this edge
		const cypher_astnode_t *r_node =
			cypher_ast_pattern_path_get_element(path, i + 1);
		const char *r_alias = AST_ToString(r_node);
		QGNode *right = QueryGraph_GetNodeByAlias(qg, r_alias);

		// retrieve the AST reference to this edge
		const cypher_astnode_t *edge =
			cypher_ast_pattern_path_get_element(path, i);
		_QueryGraphAddEdge(qg, edge, left, right, only_shortest);
	}
}

// clones path from 'qg' into 'graph'
QueryGraph *QueryGraph_ExtractPaths