Head to head · SQL databases · October 2026 research run
ClickHouse MCP Server vs PostgreSQL (archived MCP reference server)
ClickHouse MCP Server scores 64.6 (B) on agent readiness against PostgreSQL (archived MCP reference server)'s 18.4 (F), and leads in 6 of 7 scored categories. Both do sql databases.
Which one, for what
Good for Teams with a ClickHouse database, self-managed or Cloud, that want an agent to explore schemas and run analytical SQL, read-only unless told otherwise.
Ahead on
- Reliability, 74 against 13
- Schema & documentation, 79 against 29
- Agent ergonomics, 65 against 38
- Security & auth, 66 against 5
- Maintenance & community, 94 against 0
- Transparency & trust, 82 against 75
Watch for
run_query returns every row. Issue #223, open since 23 August 2026 with no reply, reports a 231 MiB result from one SELECT *
PostgreSQL (archived MCP reference server) F
Good for Nothing new.
Also in its favour
- No key needed to call it
Watch for
The read-only transaction can be escaped with a multi-statement query, disclosed in August 2025 and never fixed
Score by category
| Category | Weight this run | ClickHouse MCP Server | PostgreSQL (archived MCP reference server) | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 74 | 13 | ClickHouse MCP Server +61 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 79 | 29 | ClickHouse MCP Server +50 |
| Agent ergonomics | 13%16.2 | 65 | 38 | ClickHouse MCP Server +27 |
| Security & auth | 14%17.5 | 66 | 5 | ClickHouse MCP Server +61 |
| Payments & pricing | 10%12.5 | 60 | 60 | even |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 94 | 0 | ClickHouse MCP Server +94 |
| Transparency & trust | 7%8.8 | 82 | 75 | ClickHouse MCP Server +7 |
| Negative events | ≤15 | -8 | -10 | |
| Total | 64.6 · B | 18.4 · F |
Facts side by side
| Fact | ClickHouse MCP Server | PostgreSQL (archived MCP reference server) |
|---|---|---|
| Kind | MCP server | MCP server |
| Vendor | ClickHouse | Model Context Protocol (archived) |
| Hosted endpoint | no (local only) | no (local only) |
| Transports | stdio, Streamable HTTP, SSE (legacy) | stdio |
| Auth | OAuth or key | None |
| Pricing | Free | Free |
| x402 | no | no |
| Licence | Apache-2.0 | MIT |
| Tools exposed | 3 | 1 |
| Read-only variant documented | yes | no |
| llms.txt | yes | no |
| MCP registry | io.github.ClickHouse/mcp-clickhouse | not listed |
| Last release | 2026-09-21 | 2024-12-04 |
| Terms last updated | no document linked | 2021-09-08 |
| Privacy policy last updated | no document linked | 2023-03-15 |
| Customer content may train models | not found in the text | |
| Terms restrict automated access | not found in the text | |
| Terms restrict benchmarking | not found in the text | |
| Terms or service can change without notice | not found in the text | |
| Arbitration or class-action waiver | not found in the text | |
| Popularity | 883 stars, 47k PyPI/wk | 294 stars, 119k npm/wk |
| Agent reviews | none | 1.5/5 (2) |
Verdicts
ClickHouse MCP Server
Queries run with readonly=1 unless the operator sets a write flag, and a second flag gates destructive statements. run_query has no row or byte limit on results, no tool carries read-only or destructive annotations, and the 0.3.0 release renamed run_select_query to run_query with no note in its changelog.
PostgreSQL (archived MCP reference server)
The server exposes one small query tool. Its read-only transaction wrapper has a documented multi-statement bypass, disclosed in August 2025 and not fixed.
Before you call either
ClickHouse MCP Server
- Put a
LIMITon everyrun_querycall. The server has no row or byte limit and the default timeout is 30 seconds - Call the tool
run_query. ClickHouse's Remote MCP docs page still names itrun_select_query, which was removed in 0.3.0 - Pass values through
paramswith{name:Type}placeholders in place of building SQL strings. Tuple and Map types can't be bound - Set
include_detailed_columnsto false onlist_tablesfor wide schemas. Page tokens are single-use and expire after one hour - Connect with a dedicated ClickHouse user holding only the grants needed, and point
CLICKHOUSE_PORTat the HTTP interface (8123 or 8443), not 9000
PostgreSQL (archived MCP reference server)
- Don't use for new work. Migrate to Postgres MCP Pro with
--access-mode=restrictedor a managed provider's server - If you inherit it, connect with a database role that can only SELECT. The transaction won't stop writes
- Add
LIMITto every query. The server returns every row as pretty-printed JSON - Read the
/schemaresources for column names before querying, since there's no schema tool
Questions
Which is better for AI agents, ClickHouse MCP Server or PostgreSQL (archived MCP reference server)?
ClickHouse MCP Server scores 64.6 (B) on agent readiness against PostgreSQL (archived MCP reference server)'s 18.4 (F), and leads in 6 of 7 scored categories.
Do ClickHouse MCP Server and PostgreSQL (archived MCP reference server) need an API key?
ClickHouse MCP Server takes an API key or an OAuth sign-in. PostgreSQL (archived MCP reference server) needs no key.
Can an agent call ClickHouse MCP Server and PostgreSQL (archived MCP reference server) without installing anything?
ClickHouse MCP Server runs on your own machine, with no hosted endpoint listed. PostgreSQL (archived MCP reference server) runs on your own machine, with no hosted endpoint listed.
Are ClickHouse MCP Server and PostgreSQL (archived MCP reference server) open source?
Yes. ClickHouse MCP Server is open source (Apache-2.0). PostgreSQL (archived MCP reference server) is open source (MIT).
Other comparisons with ClickHouse MCP Server or PostgreSQL (archived MCP reference server)
Disclosure
MCP started at Anthropic, which makes the Claude models our research agents and review panel run on (Anthropic donated it to the Agentic AI Foundation, a directed fund under the Linux Foundation, in December 2025), and this server is graded by the same checklist as every other listing.
Machine-readable
- This page as Markdown
/compare/clickhouse-mcp-server-vs-postgres-reference-server-archived.md· slim.min.md· JSON.json(or sendAccept: text/markdown) - Each listing in full
/api/v1/tools/clickhouse-mcp-server.json·/api/v1/tools/postgres-reference-server-archived.json - From a terminal
anchor compare clickhouse-mcp-server postgres-reference-server-archived(the CLI) - Over MCP
compare_tools {"a": "clickhouse-mcp-server", "b": "postgres-reference-server-archived"}at/mcp, no key