MCP SQL Server


A Model Context Protocol (MCP) server for SQL Server integration with Claude Code. Query, monitor, and analyze your SQL Server databases directly from Claude.

Features

- Query Execution - Execute SELECT queries with parameterized inputs
- Schema Exploration - Browse tables, columns, procedures, and indexes
- Database Monitoring - Track active queries, blocking sessions, wait stats, and connections
- Performance Analysis - Identify missing indexes, unused indexes, and fragmentation
- Write Operations - INSERT, UPDATE, DELETE when enabled (READONLY=false)

Installation

$3

``bash
npx @fabriciofs/mcp-sql-server
`

$3

`bash
npm install -g @fabriciofs/mcp-sql-server
`

$3

`bash
git clone https://github.com/fabriciofs/mcp-sql-server.git
cd mcp-sql-server
npm install
npm run build
`

Configuration

$3

Add to your Claude Code MCP settings (~/.claude/settings.json or project .claude/settings.json):

`json
{
"mcpServers": {
"sqlserver": {
"command": "npx",
"args": ["-y", "@fabriciofs/mcp-sql-server"],
"env": {
"SQL_CONNECTION_URL": "sqlserver://user:password@localhost:1433/database",
"READONLY": "true"
}
}
}
}
`

Or with individual connection parameters:

`json
{
"mcpServers": {
"sqlserver": {
"command": "npx",
"args": ["-y", "@fabriciofs/mcp-sql-server"],
"env": {
"SQL_SERVER": "localhost",
"SQL_DATABASE": "mydb",
"SQL_USER": "sa",
"SQL_PASSWORD": "yourpassword",
"SQL_PORT": "1433",
"SQL_TRUST_CERT": "true",
"READONLY": "true"
}
}
}
}
`

$3

#### Connection (choose one method)

Method 1: Connection URL
`bash
SQL_CONNECTION_URL=sqlserver://user:password@host:port/database?TrustServerCertificate=true
`

Method 2: Individual Parameters
`bash
SQL_SERVER=localhost
SQL_DATABASE=mydb
SQL_USER=sa
SQL_PASSWORD=yourpassword
SQL_PORT=1433 # Optional, default: 1433
SQL_ENCRYPT=true # Optional, default: true
SQL_TRUST_CERT=false # Optional, default: false
`

#### Required Settings

| Variable | Description |
|----------|-------------|
| READONLY | Required. Set to true for read-only mode or false to enable write operations |

#### Optional Settings

| Variable | Default | Description |
|----------|---------|-------------|
| QUERY_TIMEOUT | 30000 | Query timeout in milliseconds (max: 120000) |
| MAX_ROWS | 1000 | Maximum rows to return (max: 5000) |
| POOL_MIN | 2 | Minimum connection pool size |
| POOL_MAX | 10 | Maximum connection pool size |
| LOG_LEVEL | info | Log level: debug, info, warn, error |

Available Tools

$3

| Tool | Description |
|------|-------------|
| sql_execute | Execute SELECT queries with parameterized inputs |

$3

| Tool | Description |
|------|-------------|
| schema_list_tables | List all tables and views in the database |
| schema_describe_table | Get detailed table information (columns, indexes, foreign keys) |
| schema_list_columns | Search for columns across all tables |
| schema_list_procedures | List stored procedures |
| schema_list_indexes | List indexes with usage statistics |

$3

| Tool | Description |
|------|-------------|
| monitor_active_queries | Monitor currently running queries |
| monitor_blocking | Monitor blocking sessions and lock chains |
| monitor_wait_stats | Monitor wait statistics for performance bottlenecks |
| monitor_database_size | Monitor database size and file usage |
| monitor_connections | Monitor active connections |
| monitor_performance_counters | Monitor SQL Server performance counters |

$3

| Tool | Description |
|------|-------------|
| analyze_query | Analyze query execution plan and statistics |
| analyze_suggest_indexes | Suggest missing indexes based on query patterns |
| analyze_unused_indexes | Find indexes that are not being used |
| analyze_duplicate_indexes | Find duplicate or overlapping indexes |
| analyze_fragmentation | Analyze index fragmentation levels |
| analyze_statistics | Analyze table statistics for stale data |

$3

| Tool | Description |
|------|-------------|
| sql_insert | Insert a row into a table |
| sql_update | Update rows in a table |
| sql_delete | Delete rows from a table |

Usage Examples

Once configured, you can ask Claude to interact with your database:

`
"List all tables in the database"
"Describe the Users table"
"Show me active queries running for more than 5 seconds"
"Find unused indexes in the Orders table"
"Analyze the fragmentation of all indexes"
"What are the top wait statistics?"
`

Security Considerations

- Always use READONLY=true in production unless write access is explicitly required
- Store credentials securely using environment variables
- Use SQL Server accounts with minimal required permissions
- Consider network security (VPN, firewall rules) for remote connections

Requirements

- Node.js >= 20.0.0
- SQL Server 2016 or later
- Appropriate SQL Server permissions for the operations you want to perform

Development

`bash


Install dependencies

npm install

Build

npm run build

Development mode (watch)

npm run dev

Type check

npm run typecheck

Run MCP Inspector

npm run inspector
``

License

MIT License - see LICENSE file for details.