apoc.hashing.fingerprinting

Function APOC Core

calculate a checksum (md5) over a node or a relationship. This deals gracefully with array properties. Two identical entities do share the same hash. MD5 is a weak hashing algorithm which is unsuitable for cryptographic use-cases.

Signature

apoc.hashing.fingerprinting(some object :: ANY?, conf = {} :: MAP?) :: (STRING?)

Input parameters

Name	Type	Default
some object	ANY?	null
conf	MAP?	{}

Name

Type

Default

some object

ANY?

null

conf

MAP?

{}

Config parameters

The procedure support the following config parameters:

Table 1. Config parameters
name	type	default	description
digestAlgorithm	String	"MD5"	The algorithm used to compute the fingerprint. Supported values are: `MD5`, `SHA-1`, `SHA-256`
strategy	String	"LAZY"	Property loading strategy. Supported values are: `LAZY` - does not include properties `EAGER` - uses all properties
nodeAllowMap	Map<String, List<String>>	{}	Properties to include per node label
nodeDisallowMap	Map<String, List<String>>	[]	Properties to exclude per node label
relAllowMap	Map<String, List<String>>	{}	Properties to include per relationship type
relDisallowMap	Map<String, List<String>>	[]	Properties to exclude per relationship type
mapAllowList	List<String>	[]	Map properties to include
mapDisallowList	List<String>	[]	Map properties to exclude
allNodesAllowList	List<String>	[]	Node properties to include
allNodesDisallowList	List<String>	[]	Node properties to exclude
allRelsAllowList	List<String>	[]	Relationship properties to include
allRelsDisallowList	List<String>	[]	Relationship properties to exclude

Usage Examples

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

MERGE (joe:Person {name: "Joe"})
MERGE (ryan:Person {name: "Ryan"})
MERGE (ryan)-[:FOLLOWS {since: datetime("2020-11-04")}]->(joe);

The following generates the fingerprint for Ryan:

MATCH (person:Person {name: "Ryan"})
RETURN apoc.hashing.fingerprinting(person) AS output;

Table 2. Results
output
"D41D8CD98F00B204E9800998ECF8427E"

The following generates the fingerprint for Ryan, using the EAGER strategy, which includes node properties:

MATCH (person:Person {name: "Ryan"})
RETURN apoc.hashing.fingerprinting(person, {
  strategy: "EAGER"
}) AS output;

Table 3. Results
output
"81C99DD6C9382C4E01A1873F9E818CE0"

The following generates the fingerprint for Ryan, excluding the name property:

MATCH (person:Person {name: "Ryan"})
RETURN apoc.hashing.fingerprinting(person, {
  allNodesDisallowList: ["name"]
}) AS output;

Table 4. Results
output
"D41D8CD98F00B204E9800998ECF8427E"

The following generates the fingerprint for Ryan, using the SHA-256 algorithm:

MATCH (person:Person {name: "Ryan"})
RETURN apoc.hashing.fingerprinting(person, {
  digestAlgorithm: "SHA-256"
}) AS output;

Table 5. Results
output
"E3B0C44298FC1C149AFBF4C8996FB92427AE41E4649B934CA495991B7852B855"

If we want less control over the generation of the fingerprint, see apoc.hashing.fingerprint.

More documentation of apoc.hashing.fingerprinting