Can not Connect to the Neo4j database using langchain.graphs import Neo4jGraph

[giuseppefutia]

Checked other resources

• I added a very descriptive title to this issue.
• I searched the LangChain documentation with the integrated search.
• I used the GitHub search to find a similar question and didn't find it.
• I am sure that this is a bug in LangChain rather than my code.
• The bug is not resolved by updating to the latest stable version of LangChain (or the specific integration package).

Example Code

I am running the following Python code:

from langchain.graphs import Neo4jGraph
graph_store = Neo4jGraph(
  url=neo4j_url,
  username=neo4j_username,
  password=neo4j_password,
  database=neo4j_database
)

However, it generates the following error:

ClientError: {code: Neo.ClientError.Database.DatabaseNotFound} {message: Database neo4j not found}

I specified a different database name in the neo4j_database variable, but it seems to still attempt to connect to a database named "neo4j".

To test the access to the database specified in the neo4j_database variable, I used the following script, and no issues or errors were raised:

from neo4j import GraphDatabase

def test_neo4j_connection(uri, user, password, database):
    driver = GraphDatabase.driver(uri, auth=(user, password))

    try:
        with driver.session(database=database) as session:
            result = session.run("RETURN 'Connection successful!' AS message")
            for record in result:
                print(record["message"])
    except Exception as e:
        print(f"Failed to connect to Neo4j: {e}")
    finally:
        driver.close()

test_neo4j_connection(neo4j_url, neo4j_username, neo4j_password, neo4j_database)

I am running the code in a colab notebook, and everything worked well until today when I re-installed everything from scratch.

Error Message and Stack Trace (if applicable)

No response

Description

It seems that langchain still attempts to connect to a database named "neo4j", also in the cases in which I specified a different database name

System Info

System Information

OS: Linux
OS Version: #1 SMP PREEMPT_DYNAMIC Thu Jun 27 21:05:47 UTC 2024
Python Version: 3.10.12 (main, Sep 11 2024, 15:47:36) [GCC 11.4.0]

Package Information

langchain_core: 0.3.6
langchain: 0.3.1
langchain_community: 0.3.1
langsmith: 0.1.128
langchain_ollama: 0.2.0
langchain_text_splitters: 0.3.0

Optional packages not installed

langgraph
langserve

Other Dependencies

aiohttp: 3.10.5
async-timeout: 4.0.3
dataclasses-json: 0.6.7
httpx: 0.27.2
jsonpatch: 1.33
numpy: 1.26.4
ollama: 0.3.3
orjson: 3.10.7
packaging: 24.1
pydantic: 2.9.2
pydantic-settings: 2.5.2
PyYAML: 6.0.2
requests: 2.32.3
SQLAlchemy: 2.0.35
tenacity: 8.5.0
typing-extensions: 4.12.2

[tomasonjo]

Can you show the code you're using?

[giuseppefutia]

To replicate the error, you can follow these steps:

pip install langchain
pip install langchain_community
pip install neo4j

url = "bolt://localhost:7687"
username ="neo4j"
password = "password"
database = "other_db"

graph = Neo4jGraph(
  url=url,
  username=username,
  password=password,
  database=database
)

graph.query("MATCH (n) RETURN n LIMIT 10")

You will notice that the query is always run against the neo4 database and not the other_db specified in the variable. Let me know if you need further details.

[giuseppefutia]

This should be the same issue: #27185

[tomasonjo]

Added a fix: #27190

[SimaIm]

I'm experiencing the same problem in my code where queries are always run against the neo4j database, even when I specify a different database name. This issue started recently, it was working correctly about two weeks ago.
@giuseppefutia Could you please share how you resolved it? Thanks

[tomasonjo]

Update to the latest version V tor., 15. okt. 2024, 22:48 je oseba SimaIm ***@***.***> napisala:

…

I'm experiencing the same problem in my code where queries are always run against the neo4j database, even when I specify a different database name. This issue started recently, it was working correctly about two weeks ago. @giuseppefutia <https://github.com/giuseppefutia> Could you please share how you resolved it? Thanks — Reply to this email directly, view it on GitHub <#26897 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEYGGTNTIMV2B2NNY5HY4P3Z3U2LXAVCNFSM6AAAAABO47FUJKVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDIMJUGM4TMMBWGA> . You are receiving this because you commented.Message ID: ***@***.***>