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Update constraint syntax, using FOR ... REQUIRE instead of ON ... ASSERT
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Co-authored-by: Therese Magnusson <[email protected]>
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HannesSandberg and Hunterness committed Aug 31, 2021
1 parent 51ccdf8 commit dd1263c
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Showing 10 changed files with 156 additions and 90 deletions.
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Expand Up @@ -917,7 +917,7 @@ Predicates that can be used to enable this optimization are:
[NOTE]
====
If there is an existence constraint on the property, no predicate is required to trigger the optimization.
For example, `CREATE CONSTRAINT constraint_name ON (p:Person) ASSERT p.name IS NOT NULL`.
For example, `CREATE CONSTRAINT constraint_name FOR (p:Person) REQUIRE p.name IS NOT NULL`.
====
Expand Down Expand Up @@ -1142,7 +1142,7 @@ Predicates that will not work:
[NOTE]
====
If there is an existence constraint on the property, no predicate is required to trigger the optimization.
For example, `CREATE CONSTRAINT constraint_name ON (p:Person) ASSERT p.name IS NOT NULL`
For example, `CREATE CONSTRAINT constraint_name FOR (p:Person) REQUIRE p.name IS NOT NULL`
As of Neo4j {neo4j-version-exact}, predicates with parameters, such as `WHERE n.prop > $param`, can trigger _index-backed order by_.
The only exception are queries with parameters of type `Point`.
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Expand Up @@ -50,6 +50,31 @@ Replaced by:
----
DROP CONSTRAINT name [IF EXISTS]
----


a|
label:syntax[]
label:added[]
[source, cypher, role="noheader"]
----
CREATE CONSTRAINT FOR ... REQUIRE ...
----
a|
New syntax for creating constraints, applicable to all constraint types.

a|
label:syntax[]
label:deprecated[]
[source, cypher, role="noheader"]
----
CREATE CONSTRAINT ON ... ASSERT ...
----
a|
Replaced by:
[source, cypher, role="noheader"]
----
CREATE CONSTRAINT FOR ... REQUIRE ...
----
|===


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8 changes: 4 additions & 4 deletions cypher/cypher-docs/src/docs/dev/glossary.asciidoc
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Expand Up @@ -24,10 +24,10 @@ This section comprises a glossary of all the keywords -- grouped by category and
|<<query-call, CALL [...YIELD]>> | Reading/Writing | Invoke a procedure deployed in the database.
|<<query-call-subquery, CALL {...}>> | Reading/Writing | Evaluates a subquery, typically used for post-union processing or aggregations.
|<<query-create, CREATE>> | Writing | Create nodes and relationships.
|<<administration-constraints-syntax, CREATE CONSTRAINT [existence] [IF NOT EXISTS] ON (n:Label) ASSERT n.property IS NOT NULL>> | Schema | Create a constraint ensuring that all nodes with a particular label have a certain property.
|<<administration-constraints-syntax, CREATE CONSTRAINT [node_key] [IF NOT EXISTS] ON (n:Label) ASSERT (n.prop1[, ..., n.propN]) IS NODE KEY [OPTIONS {optionKey: optionValue[, ...]}]>> | Schema | Create a constraint that ensures that all nodes with a particular label have all the specified properties and that the combination of property values is unique; i.e. ensures existence and uniqueness.
|<<administration-constraints-syntax, CREATE CONSTRAINT [existence] [IF NOT EXISTS] ON ()-"["r:REL_TYPE"]"-() ASSERT r.property IS NOT NULL>> | Schema | Create a constraint ensuring that all relationships with a particular type have a certain property.
|<<administration-constraints-syntax, CREATE CONSTRAINT [uniqueness] [IF NOT EXISTS] ON (n:Label) ASSERT (n.prop1[, ..., n.propN]) IS UNIQUE [OPTIONS {optionKey: optionValue[, ...]}]>> | Schema | Create a constraint that ensures the uniqueness of the combination of node label and property values for a particular property key combination across all nodes.
|<<administration-constraints-syntax, CREATE CONSTRAINT [existence] [IF NOT EXISTS] FOR (n:Label) REQUIRE n.property IS NOT NULL>> | Schema | Create a constraint ensuring that all nodes with a particular label have a certain property.
|<<administration-constraints-syntax, CREATE CONSTRAINT [node_key] [IF NOT EXISTS] FOR (n:Label) REQUIRE (n.prop1[, ..., n.propN]) IS NODE KEY [OPTIONS {optionKey: optionValue[, ...]}]>> | Schema | Create a constraint that ensures that all nodes with a particular label have all the specified properties and that the combination of property values is unique; i.e. ensures existence and uniqueness.
|<<administration-constraints-syntax, CREATE CONSTRAINT [existence] [IF NOT EXISTS] FOR ()-"["r:REL_TYPE"]"-() REQUIRE r.property IS NOT NULL>> | Schema | Create a constraint ensuring that all relationships with a particular type have a certain property.
|<<administration-constraints-syntax, CREATE CONSTRAINT [uniqueness] [IF NOT EXISTS] FOR (n:Label) REQUIRE (n.prop1[, ..., n.propN]) IS UNIQUE [OPTIONS {optionKey: optionValue[, ...]}]>> | Schema | Create a constraint that ensures the uniqueness of the combination of node label and property values for a particular property key combination across all nodes.
|<<administration-indexes-syntax, CREATE [BTREE] INDEX [single] [IF NOT EXISTS] FOR (n:Label) ON (n.property) [OPTIONS {optionKey: optionValue[, ...]}]>> | Schema | Create an index on all nodes with a particular label and a single property; i.e. create a single-property index.
|<<administration-indexes-syntax, CREATE [BTREE] INDEX [single] [IF NOT EXISTS] FOR ()-"["r:TYPE"]"-() ON (r.property) [OPTIONS {optionKey: optionValue[, ...]}]>> | Schema | Create an index on all relationships with a particular relationship type and a single property; i.e. create a single-property index.
|<<administration-indexes-syntax, CREATE [BTREE] INDEX [composite] [IF NOT EXISTS] FOR (n:Label) ON (n.prop1, ..., n.propN) [OPTIONS {optionKey: optionValue[, ...]}]>> | Schema | Create an index on all nodes with a particular label and multiple properties; i.e. create a composite index.
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12 changes: 12 additions & 0 deletions cypher/cypher-docs/src/docs/dev/ql/constraints/examples.adoc
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Expand Up @@ -127,14 +127,26 @@ include::../administration/constraints/listing-constraints-with-filtering.asciid
[[administration-constraints-deprecated-syntax]]
== Deprecated syntax

[discrete]
include::../administration/constraints/create-a-unique-constraint-using-deprecated-syntax.asciidoc[leveloffset=+1]

[discrete]
include::../administration/constraints/drop-a-unique-constraint.asciidoc[leveloffset=+1]

[discrete]
include::../administration/constraints/create-a-node-property-existence-constraint-using-deprecated-syntax.asciidoc[leveloffset=+1]

[discrete]
include::../administration/constraints/drop-a-node-property-existence-constraint.asciidoc[leveloffset=+1]

[discrete]
include::../administration/constraints/create-a-relationship-property-existence-constraint-using-deprecated-syntax.asciidoc[leveloffset=+1]

[discrete]
include::../administration/constraints/drop-a-relationship-property-existence-constraint.asciidoc[leveloffset=+1]

[discrete]
include::../administration/constraints/create-a-node-key-constraint-using-deprecated-syntax.asciidoc[leveloffset=+1]

[discrete]
include::../administration/constraints/drop-a-node-key-constraint.asciidoc[leveloffset=+1]
24 changes: 12 additions & 12 deletions cypher/cypher-docs/src/docs/dev/ql/constraints/syntax.adoc
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Expand Up @@ -32,16 +32,16 @@ This command creates a uniqueness constraint on nodes with the specified label a
[source, cypher, role=noplay]
----
CREATE CONSTRAINT [constraint_name] [IF NOT EXISTS]
ON (n:LabelName)
ASSERT n.propertyName IS UNIQUE
FOR (n:LabelName)
REQUIRE n.propertyName IS UNIQUE
[OPTIONS "{" option: value[, ...] "}"]
----

[source, cypher, role=noplay]
----
CREATE CONSTRAINT [constraint_name] [IF NOT EXISTS]
ON (n:LabelName)
ASSERT (n.propertyName_1, …, n.propertyName_n) IS UNIQUE
FOR (n:LabelName)
REQUIRE (n.propertyName_1, …, n.propertyName_n) IS UNIQUE
[OPTIONS "{" option: value[, ...] "}"]
----

Expand All @@ -53,8 +53,8 @@ This command creates a property existence constraint on nodes with the specified
[source, cypher, role=noplay]
----
CREATE CONSTRAINT [constraint_name] [IF NOT EXISTS]
ON (n:LabelName)
ASSERT n.propertyName IS NOT NULL
FOR (n:LabelName)
REQUIRE n.propertyName IS NOT NULL
----

[discrete]
Expand All @@ -65,8 +65,8 @@ This command creates a property existence constraint on relationships with the s
[source, cypher, role=noplay]
----
CREATE CONSTRAINT [constraint_name] [IF NOT EXISTS]
ON ()-"["R:RELATIONSHIP_TYPE"]"-()
ASSERT R.propertyName IS NOT NULL
FOR ()-"["R:RELATIONSHIP_TYPE"]"-()
REQUIRE R.propertyName IS NOT NULL
----

[discrete]
Expand All @@ -77,16 +77,16 @@ This command creates a node key constraint on nodes with the specified label and
[source, cypher, role=noplay]
----
CREATE CONSTRAINT [constraint_name] [IF NOT EXISTS]
ON (n:LabelName)
ASSERT n.propertyName IS NODE KEY
FOR (n:LabelName)
REQUIRE n.propertyName IS NODE KEY
[OPTIONS "{" option: value[, ...] "}"]
----

[source, cypher, role=noplay]
----
CREATE CONSTRAINT [constraint_name] [IF NOT EXISTS]
ON (n:LabelName)
ASSERT (n.propertyName_1, …, n.propertyName_n) IS NODE KEY
FOR (n:LabelName)
REQUIRE (n.propertyName_1, …, n.propertyName_n) IS NODE KEY
[OPTIONS "{" option: value[, ...] "}"]
----

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Expand Up @@ -95,12 +95,12 @@ Creating a unique constraint also creates a unique index (which is faster than a

[source, cypher]
----
CREATE CONSTRAINT person ON (person:Person) ASSERT person.id IS UNIQUE
CREATE CONSTRAINT person FOR (person:Person) REQUIRE person.id IS UNIQUE
----

[source, cypher]
----
CREATE CONSTRAINT movie ON (movie:Movie) ASSERT movie.id IS UNIQUE
CREATE CONSTRAINT movie FOR (movie:Movie) REQUIRE movie.id IS UNIQUE
----

Now importing the relationships is a matter of finding the nodes and then creating relationships between them.
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Expand Up @@ -173,7 +173,7 @@ private Collection<String> exportConstraints()
String name = quote( constraint.getName() );
String key = quote( id );
String label = quote( constraint.getLabel().name() );
result.add( "create constraint " + name + " on (n:" + label + ") assert n." + key + " is unique" );
result.add( "create constraint " + name + " for (n:" + label + ") require n." + key + " is unique" );
}
Collections.sort( result );
return result;
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