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WITH allows you to pass on data from one part of the query to the next. Whatever you list in WITH will be available in the next query part. You can use aggregation, SKIP, LIMIT, ORDER BY with WITH much like in RETURN. The only difference is that your expressions have to get an alias with AS alias to be able to access them in later query parts. That means you can chain query parts where one computes some data and the next query part can use that computed data. In your case it is what GROUP BY and HAVING would be in SQL but WITH is much more powerful than that. here is another example match (n:Employee)-[r1:WORKSIN]->(a:Team) with distinct a order by a.name limit 10 match (a)-[:INBUILDING]->(c:Property) return c.name WITH is just like RETURN just within a query. it can select, aggregate, limit, sort it's arguments. The only difference is that you need to name each expression. Any after the WITH statement only the values / variables that are passed along are accessible/visible. ...

There may be a time where many user sessions attempt to update the same property on the same node. Unlikely, but possible. This may be a 'sequence' node, where you're keeping track of an increasing identifier, a sort of autoincrement. How can you be, almost, certain that your CYPHER statement will not be blocked by another session updating the node property at that exact time? Assume the sequence node: CREATE (s:Sequences {counterToIncrement: 0}) Then call the following CYPHER MATCH (s:Sequences) CALL apoc.atomic.add(s,'counterToIncrement',1,10) YIELD newValue as seq RETURN seq This will attempt to add 1 to the sequence property 'counterToIncrement' , and will attempt up to 10 times if the property is locked, and finally the new value of 'counterToIncrement' is yielded and returned. From a post : https://community.neo4j.com/t5/neo4j-graph-platform/integer-sequence-generator-in-neo4j-apoc/td-p/19403  

MERGE is a powerful and misunderstood component of the CYPHER toolbox. Assume you have two :Person nodes each with a name property ('Adam' and 'Bob'). You might assume that you could MERGE as follows to create a [:KNOWS] relationship: MERGE (a:Person {name:'Adam'})-[r:KNOWS]->(b:Person {name:'Bob'}); and you'd be correct, it works perfectly Always remember MERGE is based on matching the entire pattern in the statement. Say you now want to set the age of Adam to 21 in the same statement. You might think it's as simple as MERGE (a:Person {name:'Adam',age:21})-[r:KNOWS]->(b:Person {name:'Bob'}); will create 2 new Person nodes and a [:KNOWS] relationship. If there is a unique constraint on :Person (name) there will be errors thrown and no new nodes or relationships. Why, the initial part of the MERGE 'looks' for a pattern match on the :Person node of name:'Adam' and age:21, it doesn't create a property. No m...

 How many Nodes and relationships are in your Graph? You could look on the left hand side of the Neo4j Browser, but that would be cheating. For nodes: MATCH (n) RETURN count(n) For Relationships: MATCH ()-[r]->() RETURN count(r) The above CYPHER statements assume all nodes and relationships are to be counted. Once you start adding in labels and relationships you will filter the return values For Outgoing Relationships: MATCH (a)-[r]->() RETURN count(a) This counts nodes with outgoing relationships only.