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Revert "Fix build error in 'build/docs/cypher/index.html'"
This reverts commit b57cca8587
as the
issue has already been fixed upstream.
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926a2bdc88
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@ -16,29 +16,19 @@ Nodes
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**Represents a record in a graph.**
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```
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()
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```
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```()```
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It's an empty *node*, to indicate that there is a *node*, but it's not relevant for the query.
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```
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(n)
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```
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```(n)```
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It's a *node* referred by the variable **n**, reusable in the query. It begins with lowercase and uses camelCase.
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```
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(p:Person)
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```
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```(p:Person)```
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You can add a *label* to your node, here **Person**. It's like a type / a class / a category. It begins with uppercase and uses camelCase.
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```
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(p:Person:Manager)
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```
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```(p:Person:Manager)```
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A node can have many *labels*.
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```
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(p:Person {name : 'Théo Gauchoux', age : 22})
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```
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```(p:Person {name : 'Théo Gauchoux', age : 22})```
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A node can have some *properties*, here **name** and **age**. It begins with lowercase and uses camelCase.
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The types allowed in properties :
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@ -50,9 +40,7 @@ The types allowed in properties :
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*Warning : there isn't datetime property in Cypher ! You can use String with a specific pattern or a Numeric from a specific date.*
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```
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p.name
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```
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```p.name```
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You can access to a property with the dot style.
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@ -61,24 +49,16 @@ Relationships (or Edges)
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**Connects two nodes**
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```
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[:KNOWS]
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```
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```[:KNOWS]```
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It's a *relationship* with the *label* **KNOWS**. It's a *label* as the node's label. It begins with uppercase and use UPPER_SNAKE_CASE.
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```
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[k:KNOWS]
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```
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```[k:KNOWS]```
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The same *relationship*, referred by the variable **k**, reusable in the query, but it's not necessary.
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```
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[k:KNOWS {since:2017}]
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```
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```[k:KNOWS {since:2017}]```
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The same *relationship*, with *properties* (like *node*), here **since**.
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```
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[k:KNOWS*..4]
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```
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```[k:KNOWS*..4]```
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It's a structural information to use in a *path* (seen later). Here, **\*..4** says "Match the pattern, with the relationship **k** which be repeated between 1 and 4 times.
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@ -87,24 +67,16 @@ Paths
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**The way to mix nodes and relationships.**
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```
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(a:Person)-[:KNOWS]-(b:Person)
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```
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```(a:Person)-[:KNOWS]-(b:Person)```
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A path describing that **a** and **b** know each other.
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```
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(a:Person)-[:MANAGES]->(b:Person)
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```
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```(a:Person)-[:MANAGES]->(b:Person)```
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A path can be directed. This path describes that **a** is the manager of **b**.
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```
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(a:Person)-[:KNOWS]-(b:Person)-[:KNOWS]-(c:Person)
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```
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```(a:Person)-[:KNOWS]-(b:Person)-[:KNOWS]-(c:Person)```
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You can chain multiple relationships. This path describes the friend of a friend.
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```
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(a:Person)-[:MANAGES]->(b:Person)-[:MANAGES]->(c:Person)
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```
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```(a:Person)-[:MANAGES]->(b:Person)-[:MANAGES]->(c:Person)```
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A chain can also be directed. This path describes that **a** is the boss of **b** and the big boss of **c**.
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Patterns often used (from Neo4j doc) :
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@ -258,19 +230,13 @@ DELETE n, r
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Other useful clauses
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---
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```
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PROFILE
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```
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```PROFILE```
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Before a query, show the execution plan of it.
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```
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COUNT(e)
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```
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```COUNT(e)```
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Count entities (nodes or relationships) matching **e**.
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```
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LIMIT x
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```
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```LIMIT x```
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Limit the result to the x first results.
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