Neo4j密码查询结构与性能优化
我已经创建了一个Cypher查询动态生成器。对于复杂的情况，此生成器会生成相当大的查询，例如：Neo4j密码查询结构与性能优化,neo4j,cypher,Neo4j,Cypher,我已经创建了一个Cypher查询动态生成器。对于复杂的情况，此生成器会生成相当大的查询，例如： MATCH (parentD)-[:CONTAINS]->(childD:Decision)-[ru:CREATED_BY]->(u:User) WHERE id(parentD) = {decisionId} MATCH (childD)<-[:SET_FOR]-(filterValue415431:Value)-[:SET_ON]->(filterCharacteris
MATCH (parentD)-[:CONTAINS]->(childD:Decision)-[ru:CREATED_BY]->(u:User)
WHERE id(parentD) = {decisionId}
MATCH (childD)<-[:SET_FOR]-(filterValue415431:Value)-[:SET_ON]->(filterCharacteristic415431:Characteristic)
WHERE id(filterCharacteristic415431) = 415431
WITH filterValue415431, childD, ru, u
WHERE ({filterValue4154311} IN filterValue415431.value )
OR ({filterValue4154312} IN filterValue415431.value )
OR ({filterValue4154313} IN filterValue415431.value )
OR ({filterValue4154314} IN filterValue415431.value )
OR ({filterValue4154315} IN filterValue415431.value )
MATCH (childD)<-[:SET_FOR]-(filterValue415441:Value)-[:SET_ON]->(filterCharacteristic415441:Characteristic)
WHERE id(filterCharacteristic415441) = 415441
WITH filterValue415441, childD, ru, u
WHERE ({filterValue4154416} IN filterValue415441.value )
OR ({filterValue4154417} IN filterValue415441.value )
OR ({filterValue4154418} IN filterValue415441.value )
OR ({filterValue4154419} IN filterValue415441.value )
OR ({filterValue41544110} IN filterValue415441.value )
OR ({filterValue41544111} IN filterValue415441.value )
OR ({filterValue41544112} IN filterValue415441.value )
OR ({filterValue41544113} IN filterValue415441.value )
OR ({filterValue41544114} IN filterValue415441.value )
OR ({filterValue41544115} IN filterValue415441.value )
OR ({filterValue41544116} IN filterValue415441.value )
OR ({filterValue41544117} IN filterValue415441.value )
MATCH (childD)<-[:SET_FOR]-(filterValue416273:Value)-[:SET_ON]->(filterCharacteristic416273:Characteristic)
WHERE id(filterCharacteristic416273) = 416273
WITH filterValue416273, childD, ru, u
WHERE (filterValue416273.value >= {filterValue41627318})
AND (filterValue416273.value <= {filterValue41627319})
MATCH (childD)<-[:SET_FOR]-(filterValue417410:Value)-[:SET_ON]->(filterCharacteristic417410:Characteristic)
WHERE id(filterCharacteristic417410) = 417410
WITH filterValue417410, childD, ru, u
MATCH (childD)<-[:SET_FOR]-(filterValue416423:Value)-[:SET_ON]->(filterCharacteristic416423:Characteristic)
WHERE id(filterCharacteristic416423) = 416423
WITH filterValue416423, childD, ru, u
WHERE ({filterValue41642320} IN filterValue416423.value )
OR ({filterValue41642321} IN filterValue416423.value )
OR ({filterValue41642322} IN filterValue416423.value )
OR ({filterValue41642323} IN filterValue416423.value )
MATCH (childD)<-[:SET_FOR]-(filterValue415673:Value)-[:SET_ON]->(filterCharacteristic415673:Characteristic)
WHERE id(filterCharacteristic415673) = 415673
WITH filterValue415673, childD, ru, u
WHERE ({filterValue41567324} IN filterValue415673.value )
OR ({filterValue41567325} IN filterValue415673.value )
OR ({filterValue41567326} IN filterValue415673.value )
OR ({filterValue41567327} IN filterValue415673.value )
OR ({filterValue41567328} IN filterValue415673.value )
OR ({filterValue41567329} IN filterValue415673.value )
OR ({filterValue41567330} IN filterValue415673.value )
OR ({filterValue41567331} IN filterValue415673.value )
OR ({filterValue41567332} IN filterValue415673.value )
OR ({filterValue41567333} IN filterValue415673.value )
OR ({filterValue41567334} IN filterValue415673.value )
OR ({filterValue41567335} IN filterValue415673.value )
OR ({filterValue41567336} IN filterValue415673.value )
OR ({filterValue41567337} IN filterValue415673.value )
OR ({filterValue41567338} IN filterValue415673.value )
OR ({filterValue41567339} IN filterValue415673.value )
OPTIONAL MATCH (childD)<-[:VOTED_FOR]-(vg:VoteGroup)-[:VOTED_ON]->(c:Criterion)
WHERE id(c) IN {criteriaIds}
WITH childD, ru, u, vg.avgVotesWeight as weight, vg.totalVotes as totalVotes
WITH ru, u, childD , toFloat(sum(weight)) as weight, toInt(sum(totalVotes)) as totalVotes
ORDER BY weight DESC
SKIP 0 LIMIT 10
RETURN ru, u, childD AS decision, weight, totalVotes,
[ (parentD)<-[:DEFINED_BY]-(entity)<-[:COMMENTED_ON]-(comg:CommentGroup)-[:COMMENTED_FOR]->(childD) |
{entityId: id(entity), types: labels(entity), totalComments: toInt(comg.totalComments)} ] AS commentGroups,
[ (parentD)<-[:DEFINED_BY]-(c1:Criterion)<-[:VOTED_ON]-(vg1:VoteGroup)-[:VOTED_FOR]->(childD) |
{criterionId: id(c1), weight: vg1.avgVotesWeight, totalVotes: toInt(vg1.totalVotes)} ] AS weightedCriteria,
[ (parentD)<-[:DEFINED_BY]-(ch1:Characteristic)<-[:SET_ON]-(v1:Value)-[:SET_FOR]->(childD) |
{characteristicId: id(ch1), value: v1.value, valueType: ch1.valueType, visualMode: ch1.visualMode} ] AS valuedCharacteristics
MATCH (parentD)-[:CONTAINS]->(childD:Decision)
WHERE id(parentD) = 415406
MATCH (childD)<-[:SET_FOR]-(filterValue416423)-[:SET_ON]->(filterCharacteristic416423)
WHERE id(filterCharacteristic416423) = 416423
WITH DISTINCT filterValue416423, childD
WHERE ('Adobe RGB' IN filterValue416423.value ) OR ('ECI RGB' IN filterValue416423.value )
MATCH (childD)<-[:SET_FOR]-(filterValue416273)-[:SET_ON]->(filterCharacteristic416273)
WHERE id(filterCharacteristic416273) = 416273
WITH DISTINCT childD, filterValue416273
WHERE (filterValue416273.value >= 4) AND (filterValue416273.value <= 53)
MATCH (childD)<-[:SET_FOR]-(filterValue415431)-[:SET_ON]->(filterCharacteristic415431)
WHERE id(filterCharacteristic415431) = 415431
WITH DISTINCT childD, filterValue415431
WHERE ('Compact' IN filterValue415431.value )
OR ('Compact SLR' IN filterValue415431.value )
OR ('Large SLR' IN filterValue415431.value )
OR ('Rangefinder-style mirrorless' IN filterValue415431.value )
OR ('SLR-like (bridge)' IN filterValue415431.value )
MATCH (childD)<-[:SET_FOR]-(filterValue415441)-[:SET_ON]->(filterCharacteristic415441)
WHERE id(filterCharacteristic415441) = 415441
WITH DISTINCT childD, filterValue415441
WHERE ('Brass' IN filterValue415441.value )
OR ('Carbon fiber' IN filterValue415441.value )
OPTIONAL MATCH (childD)<-[:VOTED_FOR]-(vg:VoteGroup)-[:VOTED_ON]->(c:Criterion)
WHERE id(c) IN [415414, 415415, 415412, 415426, 415411]
WITH DISTINCT * MATCH (childD)-[ru:CREATED_BY]->(u:User)
WITH DISTINCT childD, ru, u, vg.avgVotesWeight as weight, vg.totalVotes as totalVotes
WITH DISTINCT ru, u, childD , toFloat(sum(weight)) as weight, toInt(sum(totalVotes)) as totalVotes
ORDER BY weight DESC
SKIP 0 LIMIT 10
RETURN ru, u, childD AS decision, weight, totalVotes,
[ (parentD)<-[:DEFINED_BY]-(entity)<-[:COMMENTED_ON]-(comg:CommentGroup)-[:COMMENTED_FOR]->(childD) |
{entityId: id(entity), types: labels(entity), totalComments: toInt(comg.totalComments)} ] AS commentGroups,
[ (parentD)<-[:DEFINED_BY]-(c1:Criterion)<-[:VOTED_ON]-(vg1:VoteGroup)-[:VOTED_FOR]->(childD) |
{criterionId: id(c1), weight: vg1.avgVotesWeight, totalVotes: toInt(vg1.totalVotes)} ] AS weightedCriteria,
[ (parentD)<-[:DEFINED_BY]-(ch1:Characteristic)<-[:SET_ON]-(v1)-[:SET_FOR]->(childD) |
{characteristicId: id(ch1), value: v1.value, valueType: ch1.valueType, visualMode: ch1.visualMode} ] AS valuedCharacteristics
查询的主要问题是，您基本上进行了大量的检查，其中的行运行异常。下面是一些技巧，可以减少每次匹配时生成的行数 1） 除非您需要副本，否则请与DISTINCT一起使用，而不是仅与一起使用。使用可以创建重复的行（因为您只切断了一列），并且您处理的每个重复行都会浪费时间和额外的数据库命中。（即，删除的每个筛选器列都会添加重复的行） 2） ：Value.Value被重载。它没有语义，值甚至不能保证是任何类型。这意味着每一个：Value检查都必须进行，并接触一组：Value节点，这些节点与您搜索的内容无关。因此，随着附加：值节点数量的增加，找到合适的节点的成本就越高（如果可以对其进行索引，则成本较低，这样它就可以找到正确的：值，并查看其连接到的内容。如果您无法更改正在使用的架构，以及架构，我指的是您的数据/关系的设置方式，则这没有帮助） 3） 只检查你需要检查的东西。说（a:a）-[：to]->（b:b）似乎更有效，但如果所有[：to]都是从：a到：b，Neo4j现在必须验证第一个节点是an:a，第二个节点是a:b。Cypher不知道什么是隐式的，所以它必须进行检查，但这些冗余检查中的每一个都必须退出并针对每一行命中DB。所以最好说（a）-[：to]->（b） 4） 限制变量范围。在这里，您在开始时匹配-[ru:CREATED_BY]->（u:User），但在结束之前不使用它，没有过滤器。这会将您拥有的行数乘以每个决策的-[ru:CREATED\u by]->（u:User）数，所有这些都必须在进一步的匹配中进行检查。除非-[ru:CREATED_BY]->（u:User）以某种方式极大地限制了匹配的决策（或者每个决策只能有一个），否则请在最后匹配此支持信息 5） 按从强到弱的顺序排列过滤器（如果可以的话）。尽可能早地剪尽可能多的行 6） 最小化行的技巧。每拉出一行都会使查询中的以下步骤更加困难，因此可以最小化查询中的行。如果您正在使用或组合不相关但相似的列查询（如所有带条件A的ORG或带条件B的ORG），而这两个查询的工作只会使另一半的查询成本更高，那么最好使用UNION组合更小、更快查询的结果（UNION可以并行运行，直到合并结果）。请注意，像[1,2,3]中的WHERE org.id这样的简单查询仍然比UNION快，因为所有工作都可以在一次查找中完成 除了union之外，如果您正在收集未进行筛选的节点，则可以使用collect（列）将“重复项”减少到1行，而不是在查询结束时将（列）作为列展开以取回行！（此处的列指变量名） 7） 在一个节点上进行大量筛选？塞弗有暗示！在列上使用JOIN的提示
告诉Cypher，使用更多的起始leaf并加入它们可能会更有效地进行匹配。因此，在每个匹配项上使用usingjoinonchildd
将告诉Cypher并行执行所有过滤器，并使用所有过滤器的重叠行。请注意，使用的只是你告诉Cypher“相信我，如果我们尝试这样做，这应该会更快”，如果你错了，这实际上会使查询变得更糟。（不过，使用JOIN应该有助于使大型查询更加并行）
更新：
首先，关于node.id=“constant”和node.value=“constant”或node.id=“constant2”和node.value=“constant2”与node.value=map[node.id]的注释。第一个查询能够在节点查找时进行节点过滤，而后面的查询必须过滤所有已在其中查找的节点。如果之前没有对该查找进行过滤，则意味着贴图必须拉入所有节点。虽然映射提供了某种程度的（有争议的）简单性/灵活性，但它是过滤节点的最低效方法之一
第二，现在查询的一个大问题是：值是超重载的，而不是通过ID来查找：值应该是一个关系，或者有一个索引ID字段，这样就不必接触所有值。我认为使用Join提示至少会使SET_具有更高的优先级，这似乎是两者中效率更高的一种
下面是我试图更有效地重写概要文件查询的尝试。（v1）
MATCH（parentD）-[：CONTAINS]->（childD:Decision）
其中id（parentD）=415406
匹配（child）（过滤器特征416423）
在childD上使用JOIN
其中id（filterCharacteristic416423）=416423
其中，filterValue416423.value中的（'Adobe RGB'或filterValue416423.value中的（'ECI RGB'））
带着明显的孩子
匹配（儿童）（过滤器特征416273）
在childD上使用JOIN
其中id（filterCharacteristic416273）=416273和（filterValue416273.value>=4）和（filterValue416273.value（u:用户）
使用不同的child、ru、u、vg.avgvotes作为权重，vg.totalvoces作为totalvoces
使用不同的ru、u、childD、toFloat（总和（重量））作为权重，toInt（总和（总票数））作为总票数
按重量说明订购
跳过0限制10
返回ru、u、child作为决策、权重、总投票数，
[（家长D）在您的查询上运行配置文件并发布响应以获得更好的答案您可以在浏览器中执行时设置查询参数。请尝试：help param
和：help params
以了解用法信息。请花些时间格式化您的查询。单行上的所有内容都不可读。当然，格式化了查询。顺便问一句-有什么可以修改的吗哪一个是
Indexes
ON :Characteristic(lowerName) ONLINE
ON :CharacteristicGroup(lowerName) ONLINE
ON :Criterion(lowerName) ONLINE
ON :CriterionGroup(lowerName) ONLINE
ON :Decision(lowerName) ONLINE
ON :FlagType(name) ONLINE (for uniqueness constraint)
ON :HistoryValue(originalValue) ONLINE
ON :Permission(code) ONLINE (for uniqueness constraint)
ON :Role(name) ONLINE (for uniqueness constraint)
ON :User(email) ONLINE (for uniqueness constraint)
ON :User(username) ONLINE (for uniqueness constraint)
ON :Value(value) ONLINE
Constraints
ON ( flagtype:FlagType ) ASSERT flagtype.name IS UNIQUE
ON ( permission:Permission ) ASSERT permission.code IS UNIQUE
ON ( role:Role ) ASSERT role.name IS UNIQUE
ON ( user:User ) ASSERT user.email IS UNIQUE
ON ( user:User ) ASSERT user.username IS UNIQUE
MATCH (parentD)-[:CONTAINS]->(childD:Decision)
WHERE id(parentD) = 415406
MATCH (childD)<-[:SET_FOR]-(filterValue416423)-[:SET_ON]->(filterCharacteristic416423)
WHERE id(filterCharacteristic416423) = 416423
WITH DISTINCT filterValue416423, childD
WHERE ('Adobe RGB' IN filterValue416423.value ) OR ('ECI RGB' IN filterValue416423.value )
MATCH (childD)<-[:SET_FOR]-(filterValue416273)-[:SET_ON]->(filterCharacteristic416273)
WHERE id(filterCharacteristic416273) = 416273
WITH DISTINCT childD, filterValue416273
WHERE (filterValue416273.value >= 4) AND (filterValue416273.value <= 53)
MATCH (childD)<-[:SET_FOR]-(filterValue415431)-[:SET_ON]->(filterCharacteristic415431)
WHERE id(filterCharacteristic415431) = 415431
WITH DISTINCT childD, filterValue415431
WHERE ('Compact' IN filterValue415431.value )
OR ('Compact SLR' IN filterValue415431.value )
OR ('Large SLR' IN filterValue415431.value )
OR ('Rangefinder-style mirrorless' IN filterValue415431.value )
OR ('SLR-like (bridge)' IN filterValue415431.value )
MATCH (childD)<-[:SET_FOR]-(filterValue415441)-[:SET_ON]->(filterCharacteristic415441)
WHERE id(filterCharacteristic415441) = 415441
WITH DISTINCT childD, filterValue415441
WHERE ('Brass' IN filterValue415441.value )
OR ('Carbon fiber' IN filterValue415441.value )
OPTIONAL MATCH (childD)<-[:VOTED_FOR]-(vg:VoteGroup)-[:VOTED_ON]->(c:Criterion)
WHERE id(c) IN [415414, 415415, 415412, 415426, 415411]
WITH DISTINCT * MATCH (childD)-[ru:CREATED_BY]->(u:User)
WITH DISTINCT childD, ru, u, vg.avgVotesWeight as weight, vg.totalVotes as totalVotes
WITH DISTINCT ru, u, childD , toFloat(sum(weight)) as weight, toInt(sum(totalVotes)) as totalVotes
ORDER BY weight DESC
SKIP 0 LIMIT 10
RETURN ru, u, childD AS decision, weight, totalVotes,
[ (parentD)<-[:DEFINED_BY]-(entity)<-[:COMMENTED_ON]-(comg:CommentGroup)-[:COMMENTED_FOR]->(childD) |
{entityId: id(entity), types: labels(entity), totalComments: toInt(comg.totalComments)} ] AS commentGroups,
[ (parentD)<-[:DEFINED_BY]-(c1:Criterion)<-[:VOTED_ON]-(vg1:VoteGroup)-[:VOTED_FOR]->(childD) |
{criterionId: id(c1), weight: vg1.avgVotesWeight, totalVotes: toInt(vg1.totalVotes)} ] AS weightedCriteria,
[ (parentD)<-[:DEFINED_BY]-(ch1:Characteristic)<-[:SET_ON]-(v1)-[:SET_FOR]->(childD) |
{characteristicId: id(ch1), value: v1.value, valueType: ch1.valueType, visualMode: ch1.visualMode} ] AS valuedCharacteristics
PROFILE MATCH (parentD)-[:CONTAINS]->(childD:Decision)
WHERE id(parentD) = 415406
MATCH (childD)<-[:SET_FOR]-(filterValue416423)-[:SET_ON]->(filterCharacteristic416423)
USING JOIN ON childD
WHERE id(filterCharacteristic416423) = 416423
AND ('Adobe RGB' IN filterValue416423.value ) OR ('ECI RGB' IN filterValue416423.value )
WITH DISTINCT childD
MATCH (childD)<-[:SET_FOR]-(filterValue416273)-[:SET_ON]->(filterCharacteristic416273)
USING JOIN ON childD
WHERE id(filterCharacteristic416273) = 416273 AND (filterValue416273.value >= 4) AND (filterValue416273.value <= 53)
WITH DISTINCT childD
MATCH (childD)<-[:SET_FOR]-(filterValue415431)-[:SET_ON]->(filterCharacteristic415431)
USING JOIN ON childD
WHERE id(filterCharacteristic415431) = 415431
AND ('Compact' IN filterValue415431.value )
OR ('Compact SLR' IN filterValue415431.value )
OR ('Large SLR' IN filterValue415431.value )
OR ('Rangefinder-style mirrorless' IN filterValue415431.value )
OR ('SLR-like (bridge)' IN filterValue415431.value )
WITH DISTINCT childD
MATCH (childD)<-[:SET_FOR]-(filterValue415441)-[:SET_ON]->(filterCharacteristic415441)
USING JOIN ON childD
WHERE id(filterCharacteristic415441) = 415441
AND ('Brass' IN filterValue415441.value )
OR ('Carbon fiber' IN filterValue415441.value )
OPTIONAL MATCH (childD)<-[:VOTED_FOR]-(vg:VoteGroup)-[:VOTED_ON]->(c:Criterion)
WHERE id(c) IN [415414, 415415, 415412, 415426, 415411]
WITH DISTINCT * MATCH (childD)-[ru:CREATED_BY]->(u:User)
WITH DISTINCT childD, ru, u, vg.avgVotesWeight as weight, vg.totalVotes as totalVotes
WITH DISTINCT ru, u, childD , toFloat(sum(weight)) as weight, toInt(sum(totalVotes)) as totalVotes
ORDER BY weight DESC
SKIP 0 LIMIT 10
RETURN childD
MATCH (parentD)-[:CONTAINS]->(childD:Decision)
WHERE id(parentD) = 415406
MATCH (childD)<-[:SET_FOR]-(filterValue416423)-[:SET_ON]->(filterCharacteristic416423)
USING JOIN ON childD
WHERE id(filterCharacteristic416423) = 416423
WHERE ('Adobe RGB' IN filterValue416423.value ) OR ('ECI RGB' IN filterValue416423.value )
WITH DISTINCT childD
MATCH (childD)<-[:SET_FOR]-(filterValue416273)-[:SET_ON]->(filterCharacteristic416273)
USING JOIN ON childD
WHERE id(filterCharacteristic416273) = 416273 AND (filterValue416273.value >= 4) AND (filterValue416273.value <= 53)
WITH DISTINCT childD
MATCH (childD)<-[:SET_FOR]-(filterValue415431)-[:SET_ON]->(filterCharacteristic415431)
USING JOIN ON childD
WHERE id(filterCharacteristic415431) = 415431
WHERE ('Compact' IN filterValue415431.value )
OR ('Compact SLR' IN filterValue415431.value )
OR ('Large SLR' IN filterValue415431.value )
OR ('Rangefinder-style mirrorless' IN filterValue415431.value )
OR ('SLR-like (bridge)' IN filterValue415431.value )
WITH DISTINCT childD
MATCH (childD)<-[:SET_FOR]-(filterValue415441)-[:SET_ON]->(filterCharacteristic415441)
USING JOIN ON childD
WHERE id(filterCharacteristic415441) = 415441
WHERE ('Brass' IN filterValue415441.value )
OR ('Carbon fiber' IN filterValue415441.value )
OPTIONAL MATCH (childD)<-[:VOTED_FOR]-(vg:VoteGroup)-[:VOTED_ON]->(c:Criterion)
WHERE id(c) IN [415414, 415415, 415412, 415426, 415411]
WITH DISTINCT * MATCH (childD)-[ru:CREATED_BY]->(u:User)
WITH DISTINCT childD, ru, u, vg.avgVotesWeight as weight, vg.totalVotes as totalVotes
WITH DISTINCT ru, u, childD , toFloat(sum(weight)) as weight, toInt(sum(totalVotes)) as totalVotes
ORDER BY weight DESC
SKIP 0 LIMIT 10
RETURN ru, u, childD AS decision, weight, totalVotes,
[ (parentD)<-[:DEFINED_BY]-(entity)<-[:COMMENTED_ON]-(comg:CommentGroup)-[:COMMENTED_FOR]->(childD) |
{entityId: id(entity), types: labels(entity), totalComments: toInt(comg.totalComments)} ] AS commentGroups,
[ (parentD)<-[:DEFINED_BY]-(c1:Criterion)<-[:VOTED_ON]-(vg1:VoteGroup)-[:VOTED_FOR]->(childD) |
{criterionId: id(c1), weight: vg1.avgVotesWeight, totalVotes: toInt(vg1.totalVotes)} ] AS weightedCriteria,
[ (parentD)<-[:DEFINED_BY]-(ch1:Characteristic)<-[:SET_ON]-(v1)-[:SET_FOR]->(childD) |
{characteristicId: id(ch1), value: v1.value, valueType: ch1.valueType, visualMode: ch1.visualMode} ] AS valuedCharacteristics