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这是密码：

START n=node:ACCOUNTS(ACCOUNT_ID={id}) 
MATCH (n)-[:PROVIDER]->(p)<-[r:ALERT]-() 
RETURN r 
ORDER BY {o} ASC 
SKIP {s} LIMIT {l}

以下是执行计划：

ColumnFilter(symKeys=["  UNNAMEDS239765216", "n", "m", "  UNNAMED3", "p", "r"], returnItemNames=["r"], _rows=50, _db_hits=0)
    Slice(skip="{s}", _rows=50, _db_hits=0)
      Top(orderBy=["SortItem(Cached(  UNNAMEDS239765216 of type Any),true)"], limit="Add", _rows=50, _db_hits=0)
        Extract(symKeys=["n", "m", "  UNNAMED3", "p", "r"], exprKeys=["  UNNAMEDS239765216"], _rows=42563, _db_hits=0)
          TraversalMatcher(trail="(n)-[  UNNAMED3:PROVIDER WHERE true AND true]->(p)<-[r:ALERT WHERE true AND true]-(m)", _rows=42563, _db_hits=614381)
            ParameterPipe(_rows=1, _db_hits=0)

账户有提供者（一对多）并且提供者有传入警报关系。我只对选择这些关系感兴趣。

第一次执行需要：

2013-07-18 17:40:54,199 [main] INFO  net.ahm.graph.dao.AlertDAO  - >>>> GET ALERTS FOR ACCOUNT CYPHER TOOK: 4789 m-secs

相同查询的第 10 次执行需要（引擎被缓存，查询被参数化）：

2013-07-18 17:41:15,431 [main] INFO  net.ahm.graph.dao.AlertDAO  - >>>> GET ALERTS FOR ACCOUNT CYPHER TOOK: 1586 m-secs

删除 ORDER BY 会导致以下执行计划和时间：

2013-07-20 23:45:09,317 [main] DEBUG net.ahm.graph.dao.AlertDAO  - ColumnFilter(symKeys=["n", "m", "  UNNAMED3", "p", "r"], returnItemNames=["r"], _rows=50, _db_hits=0)
Slice(skip="{s}", limit="{l}", _rows=50, _db_hits=0)
  TraversalMatcher(trail="(n)-[  UNNAMED3:PROVIDER WHERE true AND true]->(p)<-[r:ALERT WHERE true AND true]-(m)", _rows=50, _db_hits=241)
    ParameterPipe(_rows=1, _db_hits=0)
2013-07-20 23:45:09,317 [main] INFO  net.ahm.graph.dao.AlertDAO  - >>>> GET ALERTS FOR ACCOUNT CYPHER TOOK: 9 m-secs
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