Neo4j: Do queries on specific database? - database

Question

I´m new to Neo4j, and want to implement a service that makes use of it.
I´ve read the docs and searched for it, however I still didn´t get an answer to this simple question:
How do I specify which database to query in a Neo4j query?
E.g. I connected to bolt://localhost:7687, and have three databases in there: system, neo4j, and mydb. The neo4j database is the standard.
When I open the Neo4j browser and do a query such as MATCH (n) RETURN n, it automatically assumes that I want to query the standard DB which is called neo4j. However, I want to query another one, mydb.
My output when I query aforementioned query says
{
"query": {
"text": "match (n) return n",
"parameters": {}
},
"queryType": "r",
"counters": {
"_stats": {
"nodesCreated": 0,
"nodesDeleted": 0,
"relationshipsCreated": 0,
"relationshipsDeleted": 0,
"propertiesSet": 0,
"labelsAdded": 0,
"labelsRemoved": 0,
"indexesAdded": 0,
"indexesRemoved": 0,
"constraintsAdded": 0,
"constraintsRemoved": 0
},
"_systemUpdates": 0
},
"updateStatistics": {
"_stats": {
"nodesCreated": 0,
"nodesDeleted": 0,
"relationshipsCreated": 0,
"relationshipsDeleted": 0,
"propertiesSet": 0,
"labelsAdded": 0,
"labelsRemoved": 0,
"indexesAdded": 0,
"indexesRemoved": 0,
"constraintsAdded": 0,
"constraintsRemoved": 0
},
"_systemUpdates": 0
},
"plan": false,
"profile": false,
"notifications": [],
"server": {
"address": "localhost:7687",
"version": "Neo4j/4.4.5",
"agent": "Neo4j/4.4.5",
"protocolVersion": 4.4
},
"resultConsumedAfter": {
"low": 2,
"high": 0
},
"resultAvailableAfter": {
"low": 8,
"high": 0
},
"database": {
"name": "neo4j"
}
}
In the last JSON value is the proof that the query was executed on database neo4j.
What do I have to add to my queries to instead query another database in the same DBMS?

Answer 1

You can change/specify the database using the following options.
From the Neo4j Browser, you can select the database in the sidebar.
In Cypher syntax, the use command lets you choose different databases.
:use mydb.
If you connect to Neo4j through an Application driver, you can specify the database while creating the session object.
For example, if you are using the Python driver:
from neo4j import GraphDatabase
driver = GraphDatabase.driver(uri, auth=(user, password))
session = driver.session(database="mydb")
Specify the default database in a system-wide manner by modifying the config_dbms.default_database value in the the neo4j.conf file.