apoc.meta.nodeTypeProperties

Procedure APOC Core

apoc.meta.nodeTypeProperties()

Signature

apoc.meta.nodeTypeProperties(config = {} :: MAP?) :: (nodeType :: STRING?, nodeLabels :: LIST? OF STRING?, propertyName :: STRING?, propertyTypes :: LIST? OF STRING?, mandatory :: BOOLEAN?, propertyObservations :: INTEGER?, totalObservations :: INTEGER?)

Input parameters

Name Type Default

config

MAP?

{}

Config parameters

The procedure support the following config parameters:

Table 1. Config parameters
name type default description

includeLabels

List<String>

[]

labels to include. Default is to include all labels

includeRels

List<String>

[]

relationship types to include. Default is to include all relationship types

excludeLabels

List<String>

[]

labels to exclude. Default is to not exclude any label

excludeRels

List<String>

[]

relationship types to exclude. Default is to not exclude any relationship type

sample

Long

1000

number of nodes to sample per label. See "Sampling" section below.

maxRels

Long

100

number of relationships to sample per relationship type

Sampling

Because the count stores return an incomplete picture of the data, we have to cross check the results with the actual data to filter out false positives.

We use a subset of the data to analyze by specifying the sample parameter (1000 by default).

Through this parameter, for each label we split data for each node-label into batches of (total / sample) ± rand where total is the total number of nodes with that label and rand is a number between 0 and total / sample / 10.

So, we pick a percentage of nodes with that label of roughly sample / total * 100% to check against. We pick the first node of each batch, and we analyze the properties and the relationships.

Table 2. Deprecated parameters
name type default description

labels

List<String>

[]

deprecated, use includeLabels

rels

List<String>

[]

deprecated, use includeRels

excludes

List<String>

[]

deprecated, use excludeLabels

Output parameters

Name Type

nodeType

STRING?

nodeLabels

LIST? OF STRING?

propertyName

STRING?

propertyTypes

LIST? OF STRING?

mandatory

BOOLEAN?

propertyObservations

INTEGER?

totalObservations

INTEGER?

Usage Examples

The examples in this section are based on the following sample graph:

CREATE (Keanu:Person {name:'Keanu Reeves', born:1964})
CREATE (TomH:Person {name:'Tom Hanks', born:1956})

CREATE (TheMatrix:Movie {title:'The Matrix', released:1999, tagline:'Welcome to the Real World'})
CREATE (TheMatrixReloaded:Movie {title:'The Matrix Reloaded', released:2003, tagline:'Free your mind'})
CREATE (TheMatrixRevolutions:Movie {title:'The Matrix Revolutions', released:2003, tagline:'Everything that has a beginning has an end'})
CREATE (SomethingsGottaGive:Movie {title:"Something's Gotta Give", released:2003})
CREATE (TheDevilsAdvocate:Movie {title:"The Devil's Advocate", released:1997, tagline:'Evil has its winning ways'})

CREATE (YouveGotMail:Movie {title:"You've Got Mail", released:1998, tagline:'At odds in life... in love on-line.'})
CREATE (SleeplessInSeattle:Movie {title:'Sleepless in Seattle', released:1993, tagline:'What if someone you never met, someone you never saw, someone you never knew was the only someone for you?'})
CREATE (ThatThingYouDo:Movie {title:'That Thing You Do', released:1996, tagline:'In every life there comes a time when that thing you dream becomes that thing you do'})
CREATE (CloudAtlas:Movie {title:'Cloud Atlas', released:2012, tagline:'Everything is connected'})

CREATE (Keanu)-[:ACTED_IN {roles:['Neo']}]->(TheMatrix)
CREATE (Keanu)-[:ACTED_IN {roles:['Neo']}]->(TheMatrixReloaded)
CREATE (Keanu)-[:ACTED_IN {roles:['Neo']}]->(TheMatrixRevolutions)
CREATE (Keanu)-[:ACTED_IN {roles:['Julian Mercer']}]->(SomethingsGottaGive)
CREATE (Keanu)-[:ACTED_IN {roles:['Kevin Lomax']}]->(TheDevilsAdvocate)

CREATE (TomH)-[:ACTED_IN {roles:['Joe Fox']}]->(YouveGotMail)
CREATE (TomH)-[:ACTED_IN {roles:['Sam Baldwin']}]->(SleeplessInSeattle)
CREATE (TomH)-[:ACTED_IN {roles:['Mr. White']}]->(ThatThingYouDo)
CREATE (TomH)-[:ACTED_IN {roles:['Zachry', 'Dr. Henry Goose', 'Isaac Sachs', 'Dermot Hoggins']}]->(CloudAtlas);

We can return the metadata of the database from a sample of the database contents, by running the following query:

CALL apoc.meta.nodeTypeProperties();
Table 3. Results
nodeType nodeLabels propertyName propertyTypes mandatory propertyObservations totalObservations

":`Person`"

["Person"]

"name"

["String"]

FALSE

2

2

":`Person`"

["Person"]

"born"

["Long"]

FALSE

2

2

":`Movie`"

["Movie"]

"title"

["String"]

FALSE

9

9

":`Movie`"

["Movie"]

"tagline"

["String"]

FALSE

8

9

":`Movie`"

["Movie"]

"released"

["Long"]

FALSE

9

9

We can return metadata for a subset of labels by specifying the includeLabels config parameter. The following returns the metadata for the Person label:

CALL apoc.meta.nodeTypeProperties({includeLabels: ["Person"]});
Table 4. Results
nodeType nodeLabels propertyName propertyTypes mandatory propertyObservations totalObservations

":`Person`"

["Person"]

"name"

["String"]

FALSE

2

2

":`Person`"

["Person"]

"born"

["Long"]

FALSE

2

2

We can control the sampling rate by specifying the sample parameter. The following returns metadata based on sampling up to 3 nodes per label:

CALL apoc.meta.nodeTypeProperties({sample: 3});
Table 5. Results
nodeType nodeLabels propertyName propertyTypes mandatory propertyObservations totalObservations

":`Person`"

["Person"]

"name"

["String"]

FALSE

2

2

":`Person`"

["Person"]

"born"

["Long"]

FALSE

2

2

":`Movie`"

["Movie"]

"title"

["String"]

FALSE

3

3

":`Movie`"

["Movie"]

"tagline"

["String"]

FALSE

3

3

":`Movie`"

["Movie"]

"released"

["Long"]

FALSE

3

3