TASK: Early termination of findDescendantNodes with limit1

[mhsdesign]

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• rector find usages with get 0 to the new fq using limit
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[mhsdesign]

As shown by benchmarks in #4205 (comment) the early termination doesnt have a real impact ...

i think its because we traverse the tree not level by level but each line after line which does not make the happy case that happy in general. Like in my testing i traversed 6001 instead of 6854 nodes to find a node on third level which is still too much.

[mhsdesign]

After a little debugging denny and me found out that the used attempt for termination does not work as expected:

WITH RECURSIVE tree AS
    (SELECT n.*,
         h.subtreetags,
         CAST("ROOT" AS CHAR(50)) AS parentNodeAggregateId,
         0 AS level,
         0 AS position,
         CASE
             WHEN n.nodetypename IN (:explicitlyAllowedNodeTypeNames) THEN 1
             ELSE 0 END AS isMatch
     FROM cr_default_p_graph_node n
              INNER JOIN cr_default_p_graph_hierarchyrelation h
                         ON h.childnodeanchor = n.relationanchorpoint
              INNER JOIN cr_default_p_graph_node p ON p.relationanchorpoint = h.parentnodeanchor
              INNER JOIN cr_default_p_graph_hierarchyrelation ph
                         ON ph.childnodeanchor = p.relationanchorpoint
     WHERE (h.contentstreamid = :contentStreamId)
       AND (h.dimensionspacepointhash = :dimensionSpacePointHash)
       AND (ph.contentstreamid = :contentStreamId)
       AND (ph.dimensionspacepointhash = :dimensionSpacePointHash)
       AND (p.nodeaggregateid = :entryNodeAggregateId)
       AND (NOT JSON_CONTAINS_PATH(h.subtreetags, 'one', :tagPath0))
     UNION
     SELECT cn.*,
         h.subtreetags,
         pn.nodeaggregateid AS parentNodeAggregateId,
         pn.level + 1 AS level,
         h.position,
         CASE
             WHEN cn.nodetypename IN (:explicitlyAllowedNodeTypeNames) THEN 1
             ELSE 0 END AS isMatch
     FROM tree pn
              INNER JOIN cr_default_p_graph_hierarchyrelation h
                         ON h.parentnodeanchor = pn.relationanchorpoint
              INNER JOIN cr_default_p_graph_node cn ON cn.relationanchorpoint = h.childnodeanchor
     WHERE (h.contentstreamid = :contentStreamId)
       AND (h.dimensionspacepointhash = :dimensionSpacePointHash)
       AND (pn.isMatch = 0)
       AND (NOT JSON_CONTAINS_PATH(h.subtreetags, 'one', :tagPath0)))
SELECT *
FROM tree n
WHERE n.isMatch = 1
ORDER BY level ASC, position ASC
LIMIT 1

only the AND (pn.isMatch = 0) is the termination condition and results in the behaviour of not traversing the children further of a matched node. But they dont prevent traversal if the node was already found in another branch.

[mhsdesign]

cc @kitsunet