apoc.meta.data.of
Procedure
apoc.meta.data.of(graph ANY, config MAP<STRING, ANY>)
- examines the given sub-graph and returns a table of metadata.
This procedure is not considered safe to run from multiple threads. It is therefore not supported by the parallel runtime (introduced in Neo4j 5.13). For more information, see the Cypher Manual → Parallel runtime. |
Signature
apoc.meta.data.of(graph :: ANY, config = {} :: MAP) :: (label :: STRING, property :: STRING, count :: INTEGER, unique :: BOOLEAN, index :: BOOLEAN, existence :: BOOLEAN, type :: STRING, array :: BOOLEAN, sample :: LIST<ANY>, left :: INTEGER, right :: INTEGER, other :: LIST<STRING>, otherLabels :: LIST<STRING>, elementType :: STRING)
Config Parameters
This procedure supports the following config parameters:
Name | Type | Default | Description |
---|---|---|---|
sample |
INTEGER |
1000 |
Number of nodes to sample. Setting |
Sampling
Specify the sample
parameter (1000 by default) to analyze a subset of the data.
The sample, along with the count of nodes for each label, is used to calculate a skip value. Since this value is generated using a random number generator, results obtained through the sampling method may vary between subsequent runs.
If a database contains 500 nodes with the label Foo
label, the skip count for that label is calculated as follows:
The skip count per node label is determined by generating a random number between (totalNodesForLabel / sample) ± 0.1
.
Sample 10: skipCount = 500 / 10 = 50
The resulting skip count will be between 45 and 55.
Sample 50: skipCount = 500 / 50 = 10
The resulting skip count will be between 9 and 11.
Sample 100: skipCount = 500 / 100 = 5
The resulting skip count will be 5.
The skip count represents the number of nodes skipped before one is examined. For instance, with a skip count of 5, every 5th node is examined. Consequently, a higher sample number results in more nodes being sampled.
To stop sampling set sample: -1
.
Output parameters
Name | Type |
---|---|
label |
STRING |
property |
STRING |
count |
INTEGER |
unique |
BOOLEAN |
index |
BOOLEAN |
existence |
BOOLEAN |
type |
STRING |
array |
BOOLEAN |
sample |
LIST<ANY> |
left |
INTEGER |
right |
INTEGER |
other |
LIST<STRING> |
otherLabels |
LIST<STRING> |
elementType |
STRING |
Type of supported input graphs
Type | Description |
---|---|
STRING |
a Cypher query |
Virtual Graph |
a Virtual Graph returned by |
MAP |
a map with two field |
If you want more details you can look at apoc.meta.data
documentation