Note
Brought to you by Bytebase, open-source database DevSecOps platform.
DBHub is a universal database gateway implementing the Model Context Protocol (MCP) server interface. This gateway allows MCP-compatible clients to connect to and explore different databases.
+------------------+ +--------------+ +------------------+
| | | | | |
| | | | | |
| Claude Desktop +--->+ +--->+ PostgreSQL |
| | | | | |
| Cursor +--->+ DBHub +--->+ SQL Server |
| | | | | |
| Other Clients +--->+ +--->+ SQLite |
| | | | | |
| | | +--->+ MySQL |
| | | | | |
| | | +--->+ MariaDB |
| | | | | |
+------------------+ +--------------+ +------------------+
MCP Clients MCP Server Databases
https://demo.dbhub.ai/message connects a sample employee database. You can point Cursor or MCP Inspector to it to see it in action.
Resource Name | URI Format | PostgreSQL | MySQL | MariaDB | SQL Server | SQLite |
---|---|---|---|---|---|---|
schemas | db://schemas |
✅ | ✅ | ✅ | ✅ | ✅ |
tables_in_schema | db://schemas/{schemaName}/tables |
✅ | ✅ | ✅ | ✅ | ✅ |
table_structure_in_schema | db://schemas/{schemaName}/tables/{tableName} |
✅ | ✅ | ✅ | ✅ | ✅ |
indexes_in_table | db://schemas/{schemaName}/tables/{tableName}/indexes |
✅ | ✅ | ✅ | ✅ | ✅ |
procedures_in_schema | db://schemas/{schemaName}/procedures |
✅ | ✅ | ✅ | ✅ | ❌ |
procedure_details_in_schema | db://schemas/{schemaName}/procedures/{procedureName} |
✅ | ✅ | ✅ | ✅ | ❌ |
Tool | Command Name | Description | PostgreSQL | MySQL | MariaDB | SQL Server | SQLite |
---|---|---|---|---|---|---|---|
Execute SQL | execute_sql |
Execute single or multiple SQL statements (separated by semicolons) | ✅ | ✅ | ✅ | ✅ | ✅ |
Prompt | Command Name | PostgreSQL | MySQL | MariaDB | SQL Server | SQLite |
---|---|---|---|---|---|---|
Generate SQL | generate_sql |
✅ | ✅ | ✅ | ✅ | ✅ |
Explain DB Elements | explain_db |
✅ | ✅ | ✅ | ✅ | ✅ |
# PostgreSQL example
docker run --rm --init \
--name dbhub \
--publish 8080:8080 \
bytebase/dbhub \
--transport http \
--port 8080 \
--dsn "postgres://user:password@localhost:5432/dbname?sslmode=disable"
# Demo mode with sqlite sample employee database
docker run --rm --init \
--name dbhub \
--publish 8080:8080 \
bytebase/dbhub \
--transport http \
--port 8080 \
--demo
# PostgreSQL example
npx @bytebase/dbhub --transport http --port 8080 --dsn "postgres://user:password@localhost:5432/dbname?sslmode=disable"
# Demo mode with sqlite sample employee database
npx @bytebase/dbhub --transport http --port 8080 --demo
# Demo mode with sample employee database
npx @bytebase/dbhub --transport http --port 8080 --demo
Note: The demo mode includes a bundled SQLite sample "employee" database with tables for employees, departments, salaries, and more.
- Claude Desktop only supports
stdio
transport https://github.com/orgs/modelcontextprotocol/discussions/16
// claude_desktop_config.json
{
"mcpServers": {
"dbhub-postgres-docker": {
"command": "do
8000
cker",
"args": [
"run",
"-i",
"--rm",
"bytebase/dbhub",
"--transport",
"stdio",
"--dsn",
// Use host.docker.internal as the host if connecting to the local db
"postgres://user:password@host.docker.internal:5432/dbname?sslmode=disable"
]
},
"dbhub-postgres-npx": {
"command": "npx",
"args": [
"-y",
"@bytebase/dbhub",
"--transport",
"stdio",
"--dsn",
"postgres://user:password@localhost:5432/dbname?sslmode=disable"
]
},
"dbhub-demo": {
"command": "npx",
"args": ["-y", "@bytebase/dbhub", "--transport", "stdio", "--demo"]
}
}
}
- Cursor supports both
stdio
andhttp
. - Follow Cursor MCP guide and make sure to use Agent mode.
You can specify the SSL mode using the sslmode
parameter in your DSN string:
Database | sslmode=disable |
sslmode=require |
Default SSL Behavior |
---|---|---|---|
PostgreSQL | ✅ | ✅ | Certificate verification |
MySQL | ✅ | ✅ | Certificate verification |
MariaDB | ✅ | ✅ | Certificate verification |
SQL Server | ✅ | ✅ | Certificate verification |
SQLite | ❌ | ❌ | N/A (file-based) |
SSL Mode Options:
sslmode=disable
: All SSL/TLS encryption is turned off. Data is transmitted in plaintext.sslmode=require
: Connection is encrypted, but the server's certificate is not verified. This provides protection against packet sniffing but not against man-in-the-middle attacks. You may use this for trusted self-signed CA.
Without specifying sslmode
, most databases default to certificate verification, which provides the highest level of security.
Example usage:
# Disable SSL
postgres://user:password@localhost:5432/dbname?sslmode=disable
# Require SSL without certificate verification
postgres://user:password@localhost:5432/dbname?sslmode=require
# Standard SSL with certificate verification (default)
postgres://user:password@localhost:5432/dbname
You can run DBHub in read-only mode, which restricts SQL query execution to read-only operations:
# Enable read-only mode
npx @bytebase/dbhub --readonly --dsn "postgres://user:password@localhost:5432/dbname"
In read-only mode, only readonly SQL operations are allowed.
This provides an additional layer of security when connecting to production databases.
You can use DBHub in demo mode with a sample employee database for testing:
npx @bytebase/dbhub --demo
Warning
If your user/password contains special characters, you need to escape them first. (e.g. pass#word
should be escaped as pass%23word
)
For real databases, a Database Source Name (DSN) is required. You can provide this in several ways:
-
Command line argument (highest priority):
npx @bytebase/dbhub --dsn "postgres://user:password@localhost:5432/dbname?sslmode=disable"
-
Environment variable (second priority):
export DSN="postgres://user:password@localhost:5432/dbname?sslmode=disable" npx @bytebase/dbhub
-
Environment file (third priority):
- For development: Create
.env.local
with your DSN - For production: Create
.env
with your DSN
DSN=postgres://user:password@localhost:5432/dbname?sslmode=disable
- For development: Create
Warning
When running in Docker, use host.docker.internal
instead of localhost
to connect to databases running on your host machine. For example: mysql://user:password@host.docker.internal:3306/dbname
DBHub supports the following database connection string formats:
Database | DSN Format | Example |
---|---|---|
MySQL | mysql://[user]:[password]@[host]:[port]/[database] |
mysql://user:password@localhost:3306/dbname?sslmode=disable |
MariaDB | mariadb://[user]:[password]@[host]:[port]/[database] |
mariadb://user:password@localhost:3306/dbname?sslmode=disable |
PostgreSQL | postgres://[user]:[password]@[host]:[port]/[database] |
postgres://user:password@localhost:5432/dbname?sslmode=disable |
SQL Server | sqlserver://[user]:[password]@[host]:[port]/[database] |
sqlserver://user:password@localhost:1433/dbname?sslmode=disable |
SQLite | sqlite:///[path/to/file] or sqlite:///:memory: |
sqlite:///path/to/database.db , sqlite:C:/Users/YourName/data/database.db (windows) or sqlite:///:memory: |
Extra query parameters:
authentication=azure-active-directory-access-token
. Only applicable when running from Azure. See DefaultAzureCredential.
-
stdio (default) - for direct integration with tools like Claude Desktop:
npx @bytebase/dbhub --transport stdio --dsn "postgres://user:password@localhost:5432/dbname?sslmode=disable"
-
http - for browser and network clients:
npx @bytebase/dbhub --transport http --port 5678 --dsn "postgres://user:password@localhost:5432/dbname?sslmode=disable"
Option | Environment Variable | Description | Default |
---|---|---|---|
dsn | DSN |
Database connection string | Required if not in demo mode |
transport | TRANSPORT |
Transport mode: stdio or http |
stdio |
port | PORT |
HTTP server port (only applicable when using --transport=http ) |
8080 |
readonly | READONLY |
Restrict SQL execution to read-only operations | false |
demo | N/A | Run in demo mode with sample employee database | false |
The demo mode uses an in-memory SQLite database loaded with the sample employee database that includes tables for employees, departments, titles, salaries, department employees, and department managers. The sample database includes SQL scripts for table creation, data loading, and testing.
-
Install dependencies:
pnpm install
-
Run in development mode:
pnpm dev
-
Build for production:
pnpm build pnpm start --transport stdio --dsn "postgres://user:password@localhost:5432/dbname?sslmode=disable"
The project uses Vitest for comprehensive unit and integration testing:
- Run all tests:
pnpm test
- Run tests in watch mode:
pnpm test:watch
- Run integration tests:
pnpm test:integration
DBHub includes comprehensive integration tests for all supported database connectors using Testcontainers. These tests run against real database instances in Docker containers, ensuring full compatibility and feature coverage.
- Docker: Ensure Docker is installed and running on your machine
- Docker Resources: Allocate sufficient memory (recommended: 4GB+) for multiple database containers
- Network Access: Ability to pull Docker images from registries
Note: This command runs all integration tests in parallel, which may take 5-15 minutes depending on your system resources and network speed.
# Run all database integration tests
pnpm test:integration
# Run only PostgreSQL integration tests
pnpm test src/connectors/__tests__/postgres.integration.test.ts
# Run only MySQL integration tests
pnpm test src/connectors/__tests__/mysql.integration.test.ts
# Run only MariaDB integration tests
pnpm test src/connectors/__tests__/mariadb.integration.test.ts
# Run only SQL Server integration tests
pnpm test src/connectors/__tests__/sqlserver.integration.test.ts
# Run only SQLite integration tests
pnpm test src/connectors/__tests__/sqlite.integration.test.ts
# Run JSON RPC integration tests
pnpm test src/__tests__/json-rpc-integration.test.ts
All integration tests follow these patterns:
- Container Lifecycle: Start database container → Connect → Setup test data → Run tests → Cleanup
- Shared Test Utilities: Common test patterns implemented in
IntegrationTestBase
class - Database-Specific Features: Each database includes tests for unique features and capabilities
- Error Handling: Comprehensive testing of connection errors, invalid SQL, and edge cases
Container Startup Issues:
# Check Docker is running
docker ps
# Check available memory
docker system df
# Pull images manually if needed
docker pull postgres:15-alpine
docker pull mysql:8.0
docker pull mariadb:10.11
docker pull mcr.microsoft.com/mssql/server:2019-latest
SQL Server Timeout Issues:
- SQL Server containers require significant startup time (3-5 minutes)
- Ensure Docker has sufficient memory allocated (4GB+ recommended)
- Consider running SQL Server tests separately if experiencing timeouts
Network/Resource Issues:
# Run tests with verbose output
pnpm test:integration --reporter=verbose
# Run single database test to isolate issues
pnpm test:integration -- --testNamePattern="PostgreSQL"
# Check Docker container logs if tests fail
docker logs <container_id>
The project includes pre-commit hooks to run tests automatically before each commit:
-
After cloning the repository, set up the pre-commit hooks:
./scripts/setup-husky.sh
-
This ensures the test suite runs automatically whenever you create a commit, preventing commits that would break tests.
Debug with MCP Inspector
# PostgreSQL example
TRANSPORT=stdio DSN="postgres://user:password@localhost:5432/dbname?sslmode=disable" npx @modelcontextprotocol/inspector node /path/to/dbhub/dist/index.js
# Start DBHub with HTTP transport
pnpm dev --transport=http --port=8080
# Start the MCP Inspector in another terminal
npx @modelcontextprotocol/inspector
Connect to the DBHub server /message
endpoint