Is there a way in Neo4j to create a new Database, that gets populated by some query data from another database?
For Example, I have a Database that consists of the following Nodes:
The Graph from above can be created via the following statement: (In this example imagine the graph is the full database)
CREATE (n0:Node)
CREATE (n1:Node)
CREATE (n2:Node {capital_letter: "A"})
CREATE (n3:Node)
CREATE (n4:Node)
CREATE (n5:Node)
CREATE (n6:Node {capital_letter: "B"})
CREATE (n7:Node)
CREATE (n8:Node {capital_letter: "A"})
CREATE (n9:Node {capital_letter: "B"})
CREATE (n10:Node)
CREATE (n2)-[:TRANSACTIONS]->(n0)
CREATE (n2)-[:TRANSACTIONS]->(n1)
CREATE (n2)-[:TRANSACTIONS]->(n3)
CREATE (n3)-[:TRANSACTIONS]->(n6)
CREATE (n4)-[:TRANSACTIONS]->(n2)
CREATE (n4)-[:TRANSACTIONS]->(n7)
CREATE (n6)-[:TRANSACTIONS]->(n5)
MY QUESTION:
Is there is any way to query for a sub-graph of these nodes, to then put them into a new persistent database?
For example I would like to build a new Database, with all A and B nodes, aswell as all their neighbours and all the relationships between them.
I imagine something like the following:
INSERT INTO NEW DATABASE "NEW DB"
MATCH (a {capital_letter: "A"})
OPTIONAL MATCH (a {capital_letter: "A"})-[t1]-(a_neighbours)
MATCH (b {capital_letter: "B"})
OPTIONAL MATCH (b {capital_letter: "B"})-[t2]-(b_neighbours)
RETURN a, b, t1, t2, a_neighbours, b_neighbours
Of course the above statement does not work, but is there any possibility in Neo4J to construct a Database like so?
Please note, that my Database consists of 100Mio+ Nodes so only a feasable approach is really helpful.
**My last resort would be to just query the data, export it to .csv and then construct a new database via the neo4j-admin tool https://neo4j.com/docs/operations-manual/current/tutorial/neo4j-admin-import/
I just want to know if there is another (maybe quicker) way.
In the Neo4j world, DML and DDL statements are isolated from each other. Exporting the source data either through a dump file or CSV and importing it is the only native option.
If you are connecting to Neo4j through another Programming Language, you could build logic there to read from the source Graph and write the results to the destination Graph.