Graph functions
graph.names()
Syntax |
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Description |
Lists the names of graphs in the current database. |
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Returns |
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CREATE DATABASE dba;
CREATE DATABASE dbb;
CREATE DATABASE dbc;
CREATE COMPOSITE DATABASE composite;
CREATE ALIAS composite.first FOR DATABASE dba;
CREATE ALIAS composite.second FOR DATABASE dbb;
CREATE ALIAS composite.third FOR DATABASE dbc;
RETURN graph.names() AS name
The names of all graphs on the current composite database are returned.
name |
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Rows: 3 |
graph.propertiesByName()
Syntax |
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Description |
Returns the |
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Arguments |
Name |
Type |
Description |
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The name of the graph from which all associated properties will be returned. |
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Returns |
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The properties in the returned |
CREATE DATABASE dba;
CREATE DATABASE dbb;
CREATE DATABASE dbc;
CREATE COMPOSITE DATABASE composite;
CREATE ALIAS composite.first FOR DATABASE dba
PROPERTIES {number: 1, tags: ['A', 'B']};
CREATE ALIAS composite.second FOR DATABASE dbb
PROPERTIES {number: 0, tags: ['A']};
CREATE ALIAS composite.third FOR DATABASE dbc
PROPERTIES {number: 2, tags: ['B', 'C']};
UNWIND graph.names() AS name
RETURN name, graph.propertiesByName(name) AS props
Properties for all graphs on the current composite database are returned.
name | props |
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Rows: 3 |
UNWIND graph.names() AS name
WITH name, graph.propertiesByName(name) AS props
WHERE "A" IN props.tags
CALL () {
USE graph.byName(name)
MATCH (n)
RETURN n
}
RETURN n
Returns all nodes from a subset of graphs that have a tags
property containing "A"
.
The above query uses an empty variable scope clause: CALL () { … } (introduced in Neo4j 5.23).
If you are using an older version of Neo4j, use CALL { … } instead.
For more information, see CALL subqueries → Importing variables.
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graph.byName()
Syntax |
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Description |
Returns the graph reference of the given name. It is only supported in the |
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Arguments |
Name |
Type |
Description |
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The name of the graph to be resolved. |
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Returns |
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UNWIND graph.names() AS graphName
CALL () {
USE graph.byName(graphName)
MATCH (n)
RETURN n
}
RETURN n
Returns all nodes from all graphs on the current composite database.
The above query uses an empty variable scope clause: CALL () { … } (introduced in Neo4j 5.23).
If you are using an older version of Neo4j, use CALL { … } instead.
For more information, see CALL subqueries → Importing variables.
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graph.byElementId()
Syntax |
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Description |
Returns the graph reference with the given element id. It is only supported in the |
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Arguments |
Name |
Type |
Description |
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An element id of a node or relationship. |
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Returns |
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If the constituent database is not a standard database in the DBMS, an error will be thrown. |
In this example, it is assumed that the DBMS contains a composite database constituent, which contains the element id 4:c0a65d96-4993-4b0c-b036-e7ebd9174905:0
.
USE graph.byElementId("4:c0a65d96-4993-4b0c-b036-e7ebd9174905:0")
MATCH (n) RETURN n