how do I use cipher to query time range for neo4j nodes?

Question

I have the following:

@neo.execute_query("match (node) where node.value = 'Rachel' return node.uuid, node.epoch_utc_i, node.value")

 => {"columns"=>["node.uuid", "node.epoch_utc_i", "node.value"], "data"=>[["87f7d4c7-c161-4ba2-bce6-8c3c5104f60c", 1493774726, "Rachel"], ["23574509-3d67-4783-a00a-66a2b49b5cbd", 1493968856, "Rachel"], ["e7f01367-baa6-431b-8760-1979c215d777", 1494035989, "Rachel"], ["4cc0f450-a1c4-4992-85c1-9bcb4d759d6a", 1494047641, "Rachel"], ["e3a83a43-3b0f-4a7f-944b-4f582fb47b72", 1494183024, "Rachel"], ["1d8be261-e788-449c-9fa1-9db82816fa37", 1494531971, "Rachel"]]}

However, I am unable to use WHERE to return only those with the epoch_utc_i time between Today and Yesterday, for example:

2.2.1 :045 > yesterday = Chronic.parse('1 day ago').to_i
 => 1494906466 

2.2.1 :046 > @neo.execute_query("match (node) where node.value Contains 'Rachel' AND node.epoch_utc_i > yesterday return node.uuid, node.epoch_utc_i, node.value")
Neography::SyntaxException: NeographyError: 
--message: Variable `yesterday` not defined (line 1, column 72 (offset: 71))

Edit: tried passing the value into the query

@neo.execute_query("match (node)-[:gratefulFor]->(node2) where node.bot_client_id = 'aiaas-1409611358153-user-0149' AND node2.epoch_utc_i > $yesterday return node.bot_client_id, node2.epoch_utc_i, node2.value", {:yesterday => yesterday})

Neography::SyntaxException: NeographyError: 
--message: Variable `$yesterday` not defined (line 1, column 121 (offset: 120))

--request: {:path=>"/db/data/cypher", :body=>"{\"query\":\"match (node)-[:gratefulFor]->(node2) where node.bot_client_id = 'aiaas-1409611358153-user-0149' AND node2.epoch_utc_i > $yesterday return node.bot_client_id, node2.epoch_utc_i, node2.value\",\"params\":{\"yesterday\":1494908349}}"},

Question:

How could I achieve as I intended in my code above, only those nodes where the epoch time is greater than the epoch time for yesterday?

Answer 1

You would have to pass the variable to the query. Parameters are passed to Cypher queries using $yesterday or {yesterday} (old notation). The query will be as follows:

MATCH (node) WHERE node.value 
CONTAINS 'Rachel' AND node.epoch_utc_i > {yesterday} 
RETURN node.uuid, node.epoch_utc_i, node.value"

The query execution will be passed the yesterday variable and interpolated into the query above.

@neo.execute_query(query, {:yesterday => yesterday})