Getting started with cypher
Remarks#
Cypher is a declarative graph query language that allows for expressive and efficient querying and updating of a property graph.
Cypher was originally created by Neo Technology for its graph database Neo4j, but was opened up through the openCypher project in October 2015 and has since been adopted by several other graph database vendors, including SAP HANA and AgensGraph.
Versions#
| Version | Release |
|---|---|
| 3.2 | 2017-05-11 |
| 3.1 | 2016-12-13 |
| 3.0 | 2016-04-26 |
| 2.3 | 2015-10-21 |
Keyword Guide
Read Keywords
| KeyWord | Function | Example |
|---|---|---|
| MATCH | Find following expression in graph | MATCH (n) |
Write Keywords
| KeyWord | Function | Example |
|---|---|---|
| CREATE | Create the following pattern | CREATE (n:Person{name:“Bob”}) |
| DELETE | Delete the following nodes/relationships | DELETE n |
| DETACH DELETE | Delete the following nodes, and any attached relationships | DETACH DELETE n |
Read-Write Keywords
| KeyWord | Function | Example |
|---|---|---|
| Merge | Match following pattern, or create it | Merge (n:Person{id:1337}) |
Filter Keywords
| KeyWord | Function | Example |
|---|---|---|
| Limit | Limit result rows to the following number. Combine with Skip to page results | Limit 25 |
| Skip | Skip first n result rows. Combine with Limit to page results | Skip 25 |
| WHERE | Filter results by following expression | WHERE n.age > 21 |
| AND/OR | And/Or multiple expressions | WHERE n.age > 21 AND n.age < 30 |
| NOT | Negate following expression | WHERE NOT n.age > 21 |
| ANY/ALL/NONE/SINGLE | Filter based on collection | WHERE ALL (p in people |
Remember to check the Refcard for your version of Cypher, as these may have changed.