Maps

Neo4j has the concept of Maps. It makes it easy to communicate with client-programs that can take json as input.

RETURN {name:"jan",age:56,courses:["neo4j","prob. theory",
"stochastic models","data analytics"]}

Maps can even be nested:

RETURN {name:"jan",age:56,lectures:{neo4j:3,probtheory:15,
stochasticmodels:10,dataanalytics:5}}

This map can be assigned to a variable in order to be used in Cyper or APOC :

:param data => [{name:'Michael',age: 21}]

:param teaching => [ {name:"jan",age:56,lectures:{neo4j:3,probtheory:15,stochasticmodels:10,dataanalytics:5}}]

APOC has many procedures to work with maps:

RETURN apoc.map.flatten($teaching[0])

We can remove the key lectures from the map :

RETURN apoc.map.clean($teaching[0],["lectures"],[])

Apoc can be used to create maps. For example to create a map from a list:

RETURN apoc.map.fromLists(["person1","person2"],["Jan","Mieke"])

Last change: Oct 30, 2023