neo4j - Neo4j WHERE 导致重复？

Question

我正在运行 Neo4j Desktop v1.4.1，数据库是 4.2.1 企业版。

我有一个展示位置、活动和展示位置与活动“包含”关系的简单图表。这是一个新的数据集，每个节点都是唯一的。一些展示位置“包含”数千个广告系列，因此我想通过广告系列 ID 的包含列表过滤返回的广告系列。

当我返回所有匹配的节点时，它可以工作：

neo4j@neo4j> MATCH (:Placement {id: 5})-[:CONTAINS]->(c:Campaign)
             WHERE c.id IN [400,263,150470,25810,37578]
             RETURN *;
+--------------------------+
| c                        |
+--------------------------+
| (:Campaign {id: 37578})  |
| (:Campaign {id: 263})    |
| (:Campaign {id: 25810})  |
| (:Campaign {id: 150470}) |
+--------------------------+

当我只请求活动：id 时，我得到重复：

neo4j@neo4j> MATCH (:Placement {id: 5})-[:CONTAINS]->(c:Campaign)
             WHERE c.id IN [400,263,150470,25810,37578]
             RETURN c.id;
+--------+
| c.id   |
+--------+
| 150470 |
| 150470 |
| 150470 |
| 150470 |
+--------+

展示位置 5 和广告系列 15070 之间只有一个 CONTAINS 关系：

neo4j@neo4j> MATCH (:Placement {id: 5})-[rel:CONTAINS]->(:Campaign {id:150470}) 
             RETURN count(rel);
+------------+
| count(rel) |
+------------+
| 1          |
+------------+

EXPLAIN 返回以下查询计划，cache[c.id]似乎它可能是罪魁祸首？

+---------------------------+------------------------------------------------------------------------------------------------------+----------------+---------------------+
| Operator                  | Details                                                                                              | Estimated Rows | Other               |
+---------------------------+------------------------------------------------------------------------------------------------------+----------------+---------------------+
| +ProduceResults@neo4j     | `c.id`                                                                                               |              4 | Fused in Pipeline 1 |
| |                         +------------------------------------------------------------------------------------------------------+----------------+---------------------+
| +Projection@neo4j         | cache[c.id] AS `c.id`                                                                                |              4 | Fused in Pipeline 1 |
| |                         +------------------------------------------------------------------------------------------------------+----------------+---------------------+
| +Expand(Into)@neo4j       | (anon_7)-[anon_27:CONTAINS]->(c)                                                                     |              4 | Fused in Pipeline 1 |
| |                         +------------------------------------------------------------------------------------------------------+----------------+---------------------+
| +MultiNodeIndexSeek@neo4j | UNIQUE anon_7:Placement(id) WHERE id = $autoint_0, cache[c.id], UNIQUE c:Campaign(id) WHERE id IN $a |             25 | In Pipeline 0       |
|                           | utolist_1, cache[c.id]                                                                               |                |                     |
+---------------------------+------------------------------------------------------------------------------------------------------+----------------+---------------------+

编辑：如果我在查询前加上CYPHER runtime=SLOTTED我得到预期的输出：

+--------+
| c.id   |
+--------+
| 37578  |
| 263    |
| 25810  |
| 150470 |
+--------+

如果我省略 WHERE 子句，我会得到唯一的广告系列 ID（但太多）。我觉得我遗漏了一些明显的东西，但我已经阅读了 neo4j 文档但我没有得到它。谢谢！

标签： neo4jcypher-shell