我有一个用例，我试图通过使用Cypher中的RETURN CASE WHEN THEN子句根据WHEN结果运行不同的查询来优化Neo4j数据库调用和代码。

MATCH (n {email: 'abc123@abc.com'}) 
RETURN  
CASE WHEN n.category='Owner' THEN  MATCH '(n)-[r:OWNS]->(m)'  
WHEN n.category='Dealer' THEN MATCH (n)-[r:SUPPLY_PARTS_FOR]->(m) 
WHEN n.category='Mechanic' THEN MATCH (n)-[r:SERVICE]-(m) END 
AS result;

我不确定这是否法律的，但这是我想要实现的。我遇到了语法错误，如无效输入'〉'。我如何才能以最佳方式实现这一点？编辑可能的APOC解决方案：这是我在发现FOREACH的局限性之前的计划...

MATCH (user:Person {email:{paramEmail}})
FOREACH (_ IN case when 'Owner' = {paramCategory} then [1] else [] end|
SET user:Owner, user += queryObj 
WITH user, {paramVehicles} AS coll
UNWIND coll AS vehicle
MATCH(v:Vehicles {name:vehicle}) 
CREATE UNIQUE (user)-[r:OWNS {since: timestamp()}]->(v)
SET r += paramVehicleProps 
)
FOREACH (_ IN case when 'Mechanic' = {Category} then [1] else [] end|
SET user:Owner, user += queryObj 
WITH user, {paramVehicles} AS coll
….
)
FOREACH (_ IN case when 'Dealer' = {paramCategory} then [1] else [] end|
SET user:Owner, user += queryObj 
WITH user, {paramVehicles} AS coll
…...

)
RETURN user,
CASE {paramCategory}

WHEN 'Owner' THEN [(n)-[r:OWNS]->(m) | m and r]
 WHEN 'Dealer' THEN [(n)-[r:SUPPLY_PARTS_FOR]->(m) | m] 
WHEN 'Mechanic' THEN [(n)-[r:SERVICE]-(m) | m]
 END AS result`,{
 paramQueryObj: queryObj,
 paramVehicles: makeVehicleArray,
 paramVehicleProps: vehiclePropsArray,
 paramSalesAgent: dealerSalesAgentObjarray,
 paramWarehouseAgent: dealerWarehouseAgentObjarray
}).....

有人知道用apoc.do.when（）转换吗？注意我需要在第一个THEN中使用“m”和“r”。