neo4j
apoc.meta.data() reports wrong property type information
Replication that worked for me:
create (:A { x: 1 }), (:A { x: 'Foo' });
create (:B { x: 'Foo' }), (:B { x: 'Foo' }), (:B { x: 1 });
CALL apoc.meta.data();
This setup is intentionally to confuse APOC. For both labels A and B, the property X is typed both string and long.
The APOC call:
This procedure uses a sampling configuration as specified by the config parameters, which is a MetaConfig object. The sampling appears respected, but the property type information stored in the MetaResult class is "last type in wins".
I would say this behavior is incorrect. There are two possible correct behaviors:
- Return an array of different types the property could have, as observed in the sample ["Long", "String"]
- Perform some type-coercion, and always report "String" as a single property type, because it is the widest of all observed types.
I found this because the issue is related to a PR in progress. In that PR APOC will have different stored procs that return the array of encountered types (fix suggestion 1) . https://github.com/neo4j-contrib/neo4j-apoc-procedures/pull/1318
for the type field I would probably coerce to string
and add another field types that has the full list either single element or multi
One could also report a dynamic union type of all observed types. That would be closer to how Cypher thinks about it.
