MCP DB Analyzer

A Model Context Protocol (MCP) server that gives AI assistants deep visibility into your databases. It inspects schemas, detects index problems, analyzes table bloat/fragmentation, and explains query plans — so your AI can give you actionable database optimization advice instead of generic suggestions.

SupportsPostgreSQL,MySQL, andSQLite.

There are dozens of database MCP servers — most areCRUD gateways(run queries, list tables). This toolanalyzesyour database: schema problems, missing indexes, bloated tables, slow queries, vacuum health.

Other analytical MCP servers (CrystalDBA, pg-dash, MCP-PostgreSQL-Ops) cover PostgreSQL only.MCP DB Analyzer is the only analytical MCP server that supports PostgreSQL, MySQL, and SQLitein a singlenpxinstall — no Python, no Go, no Docker.

- 9 MCP toolsfor comprehensive database analysis
- PostgreSQL + MySQL + SQLitesupport via--driverflag
- Read-only by design— all queries wrapped in READ ONLY transactions
- Markdown outputoptimized for LLM consumption
- Zero configuration— just setDATABASE_URL

Generate exportable diagnostic reports (HTML + PDF)with a Pro license key.

- Full JVM thread dump analysis report with actionable recommendations
- PDF export for sharing with your team
- Priority support

Pro license key activates thegenerate_reportMCP tool in mcp-jvm-diagnostics.

Set theDATABASE_URLenvironment variable:

export DATABASE_URL="postgresql://user:password@localhost:5432/mydb"

Or use individual PG variables:PGHOST,PGPORT,PGDATABASE,PGUSER,PGPASSWORD.

SetDATABASE_URLwith a MySQL connection string and pass--driver mysql:

export DATABASE_URL="mysql://user:password@localhost:3306/mydb" mcp-db-analyzer --driver mysql

Or use individual MySQL variables:MYSQL_HOST,MYSQL_PORT,MYSQL_DATABASE,MYSQL_USER,MYSQL_PASSWORD.

You can also setDB_DRIVER=mysqlas an environment variable instead of passing the flag.

Pass a file path viaDATABASE_URLand use--driver sqlite:

export DATABASE_URL="/path/to/database.db" mcp-db-analyzer --driver sqlite

Add to~/.claude/claude_desktop_config.json:

{ "mcpServers": { "db-analyzer": { "command": "npx", "args": ["-y", "mcp-db-analyzer"], "env": { "DATABASE_URL": "postgresql://user:password@localhost:5432/mydb" } } } }

{ "mcpServers": { "db-analyzer": { "command": "npx", "args": ["-y", "mcp-db-analyzer", "--driver", "mysql"], "env": { "DATABASE_URL": "mysql://user:password@localhost:3306/mydb" } } } }

{ "mcpServers": { "db-analyzer": { "command": "npx", "args": ["-y", "mcp-db-analyzer", "--driver", "sqlite"], "env": { "DATABASE_URL": "/path/to/database.db" } } } }

Once configured, try these prompts in Claude:
- "Show me the schema and how tables are related"— Returns table structures, foreign keys, and identifies orphan tables
- "Are there any slow queries or missing indexes?"— Ranks slow queries by execution time and suggests indexes to add
- "How many connections are active? Are any queries blocked?"— Shows connection pool utilization, idle-in-transaction sessions, and blocked queries

List all tables with row counts and sizes, or drill into a specific table's columns, types, constraints, and foreign keys.

- table(optional) — Table name to inspect. Omit to list all tables.
- schema(default:"public") — Database schema.

> inspect_schema ## Tables in schema 'public' | Table | Rows (est.) | Total Size | |-------------|-------------|------------| | users | 12,450 | 3.2 MB | | orders | 89,100 | 18.4 MB | | order_items | 245,000 | 12.1 MB |

> inspect_schema table="users" ## Table: public.users - Rows (est.): 12,450 - Total size: 3.2 MB ### Columns | # | Column | Type | Nullable | Default | |---|--------|---------------|----------|---------| | 1 | id | integer | NO | nextval | | 2 | email | varchar(255) | NO | - | | 3 | name | varchar(100) | YES | - |

Find unused indexes wasting disk space and missing indexes causing slow sequential scans. Also detects unindexed foreign keys.

- schema(default:"public") — Database schema.
- mode("usage"|"missing"|"all", default:"all") — Analysis mode.

> analyze_indexes ### Unused Indexes (2 found) | Table | Index | Size | Definition | |-------|--------------------|--------|-------------------------------| | users | idx_users_legacy | 1.2 MB | CREATE INDEX ... (old_col) | ### Unindexed Foreign Keys (1 found) | Table | Column | FK → | Constraint | |-------------|---------|--------|-------------------| | order_items | user_id | users | fk_items_user_id |

Run EXPLAIN on a SQL query and get a formatted execution plan with cost estimates, node types, and optimization warnings. Optionally run EXPLAIN ANALYZE for actual timing (SELECT queries only).

- sql— The SQL query to explain.
- analyze(default:false) — Run EXPLAIN ANALYZE (executes the query; SELECT only).

> explain_query sql="SELECT  FROM orders WHERE status = 'pending'" ## Query Plan Analysis - Estimated Total Cost: 1234.56 - Estimated Rows: 500 ### Plan Tree → Seq Scan on orders (cost=0..1234.56 rows=500) Filter: (status = 'pending') ### Potential Issues - Sequential Scan on orders (~500 rows). Consider adding an index.

> analyze_table_bloat ### Tables Needing VACUUM (1 found) | Table | Live Tuples | Dead Tuples | Bloat % | Size | Last Vacuum | |-----------|-------------|-------------|---------|-------|-------------| | audit_log | 8,000 | 2,000 | 20.0% | 10 MB | Never | ### Recommended Actions VACUUM ANALYZE public.audit_log;

> suggest_missing_indexes ### Tables Missing Indexes (1 found) | Table | Seq Scans | Index Scans | Rows | Size | |--------|-----------|-------------|--------|-------| | events | 5,000 | 0 | 50,000 | 25 MB | ### Unused Indexes (1 found) | Table | Index | Size | Definition | |-------|------------------|------|----------------------------------| | users | idx_users_legacy | 8 kB | CREATE INDEX ... (legacy_col) | DROP INDEX public.idx_users_legacy;

> analyze_slow_queries ## Slow Query Analysis (by avg execution time) | # | Avg Time | Total Time | Calls | Avg Rows | Query | |---|----------|------------|-------|----------|-------| | 1 | 150.0ms | 750000ms | 5000 | 5 | SELECT  FROM orders WHERE status = $1 | | 2 | 200.0ms | 40000ms | 200 | 2 | SELECT u.* FROM users u JOIN orders o... | ### Recommendations - 2 high-impact queries — called >100 times with >100ms avg - 2 queries returning few rows but slow — likely missing indexes

Analyze active database connections. Detects idle-in-transaction sessions, long-running queries, lock contention, and connection pool utilization. PostgreSQL and MySQL only.

> analyze_connections ## Connection Analysis (PostgreSQL) ### Connection States | State | Count | |-------|-------| | active | 3 | | idle | 12 | | idle in transaction | 2 | | Total | 17 | Max connections: 100 Utilization: 17.0% ### Idle-in-Transaction Connections | PID | User | Duration | Query | |------|------|----------|-------| | 1234 | app | 00:05:30 | UPDATE orders SET status = $1 |

Analyze foreign key relationships between tables. Builds a dependency graph showing entity connectivity, orphan tables (no FKs), cascading delete chains, and hub entities.

- schema(default:"public") — Database schema.

> analyze_table_relationships ## Table Relationships Tables: 5 Foreign Keys: 4 ### Entity Connectivity | Table | Incoming FKs | Outgoing FKs | Total | |-------|-------------|-------------|-------| | users hub | 5 | 0 | 5 | | orders | 1 | 2 | 3 | ### Orphan Tables (no FK relationships) - audit_log ### Cascading Delete Chains - users → cascades to: orders, addresses - orders → further cascades to: order_items

Analyze PostgreSQL VACUUM maintenance status. Checks dead tuple ratios, vacuum staleness, autovacuum configuration, and identifies tables needing manual VACUUM.PostgreSQL only.

- Tables with high dead tuple ratios (>10% warning, >20% critical)
- Tables never vacuumed or analyzed
- Autovacuum disabled globally
- Autovacuum configuration issues

- Findings grouped by severity (CRITICAL / WARNING / INFO)
- Tables needing VACUUM with dead tuple percentages
- Full vacuum history per table
- Autovacuum configuration settings

- All queries are wrapped in READ ONLY transactions by default
- EXPLAIN ANALYZEis restricted toSELECTqueries only
- DDL/DML statements are rejected in ANALYZE mode
- No data modification queries are allowed
- Clone the repo
- npm install
- npm run build— TypeScript compilation
- npm test— Run unit tests (vitest)
- npm run dev— Watch mode for development

- Read-only: All queries use read-only connections. Cannot modify data or schema.
- pg_stat_statements required: Slow query analysis on PostgreSQL requires thepg_stat_statementsextension to be installed and loaded.
- MySQL performance_schema: Index usage and scan statistics requireperformance_schemato be enabled (off by default in some MySQL installations).
- SQLite: No index usage statistics available (SQLite doesn't track this). Sequential scan analysis and slow query detection are not supported for SQLite.
- Large databases: Schema inspection on databases with 500+ tables may produce very long output. Use theschemaparameter to limit scope.
- Table name parameterization: SQLite PRAGMA statements use string interpolation for table names (SQLite does not support parameterized PRAGMAs). Table names are sourced fromsqlite_mastersystem table.
- Cross-database queries: Cannot analyze queries that span multiple databases or use database links.
- Estimated row counts: MySQLTABLE_ROWSininformation_schemais an estimate, not exact.
- Schema scope: All tools default topublicschema. Non-public schemas require explicit specification. Multi-schema analysis requires running tools per schema separately.
- Connection analysis:analyze_connectionsis PostgreSQL/MySQL only. Not available for SQLite databases.
- Vacuum analysis:analyze_vacuumis PostgreSQL only. For MySQL, useOPTIMIZE TABLEoranalyze_table_bloat.

- mcp-spring-boot-actuator— Spring Boot health, metrics, and bean analysis
- mcp-jvm-diagnostics— Thread dump and GC log analysis
- mcp-redis-diagnostics— Redis memory, slowlog, and client diagnostics
- mcp-migration-advisor— Flyway/Liquibase migration risk analysis

This MCP server is no longer maintained or distributed. The Corporation has pivoted to Apify marketplace actors. Seeirrationalwayson Apifyandirrcorp/bzp-poland-tendersfor current Corporation work.

Interact with PostgreSQL, MySQL, MariaDB, and SQLite databases using SQLAlchemy.