clickhouse-analytics

clickhouse-analytics is a skill for Claude Code, Codex from ericrisco/rsc-harness. It costs 86 tokens per session (2,935 once invoked), scanned A, original, MIT.

A guide to using ClickHouse, a database server built for storing large streams of events, logs, and measurements and quickly summarising them.

In plain words
What is it for?
It helps choose table storage and sorting rules, load very large datasets, create precomputed summaries, and fix queries that read more data than necessary.
Why use it?
It helps avoid slow analytics queries and poor table layouts when data grows to millions or billions of rows. It also separates this work from app databases and local file analysis.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit It helps choose table storage and sorting rules, load very large datasets, create precomputed summaries, and fix queries that read more data than necessary.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/ericrisco/rsc-harness/clickhouse-analytics
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add ericrisco/rsc-harness --skill clickhouse-analytics
Clone the repo
git clone --depth 1 https://github.com/ericrisco/rsc-harness

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for clickhouse-analytics

README.md
[![agentmods](https://agentmods.dev/badge/skills/ericrisco/rsc-harness/clickhouse-analytics.svg)](https://agentmods.dev/skills/ericrisco/rsc-harness/clickhouse-analytics)
Your own site
<a href="https://agentmods.dev/skills/ericrisco/rsc-harness/clickhouse-analytics"><img src="https://agentmods.dev/badge/skills/ericrisco/rsc-harness/clickhouse-analytics.svg" alt="Measured on agentmods" height="20"></a>
Per session 86 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,935 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00086 $0.02935
Opus 5 $0.00043 $0.01468
Sonnet 5 $0.00017 $0.00587
Haiku 4.5 $0.00009 $0.00294

Measured 8d ago against content hash f960bff9e550, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

clickhouse-analytics scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/verify.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/clickhouse-analytics/SKILL.md · 160 lines

How it starts

The opening of the file, as written. The whole thing — 160 lines — stays where its author put it; the contents beside it link to each section on GitHub.

ClickHouse analytics

ClickHouse is a multi-user, always-on, replicated columnar server built to ingest continuous high-volume writes and answer aggregation queries over billions of rows in milliseconds. You reach for it when the workload is "append a firehose of events/logs/metrics, then GROUP BY them for dashboards." Target 26.3 LTS (v26.3.12.3, 2026-05-22) — several defaults below changed in the 26.x line, so version matters.

The fork before you write any DDL: files on a laptop, in-process, no server, no concurrent writers → ../duckdb/SKILL.md; app CRUD, point updates, foreign keys, row locks, RLS, migrations → ../postgresdb/SKILL.md; clickhouse-server, replication, concurrent writers, 100M+ rows/s ingest → this skill.

Instrumenting capture (GA4/PostHog) is ../analytics/SKILL.md; charting the result for humans is ../dashboard/SKILL.md; deciding which metrics matter is ../kpi-framework/SKILL.md. ClickHouse is the engine underneath all three.

Pick the engine first

The engine decides dedup and merge behavior, and you cannot change ORDER BY/PARTITION BY later without a rebuild — so choose before typing CREATE TABLE.

Engine Use it for Dedup / merge behavior Gotcha
MergeTree Append-only events, logs, metrics No dedup of logical rows; inserts dedup'd by block since 26.2 The default and 90% of tables
ReplacingMergeTree(ver) Upserts / keep latest version per key Collapses duplicate ORDER BY keys eventually during merges Reads see dupes until merged; need FINAL to force — slow, keep off hot path
AggregatingMergeTree Pre-aggregated rollups fed by a materialized view Merges -State partials per ORDER BY key Only useful behind an MV; query with -Merge
SummingMergeTree Simple additive rollups (sum only) Sums numeric columns per ORDER BY key on merge Can't do uniq/quantile — use AggregatingMergeTree for those
Replicated* prefix High availability / multi-replica Same as base engine + ZooKeeper/Keeper replication Production HA wrapper; combine with any of the above

Read the full file on GitHub · 160 lines

Files

What ships with it

6 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 8d ago First seen · 160 lines · 86 tokens per session scan A f960bff9e550

Subscribe to this mod's changes

clickhouse-analytics is a skill published in the GitHub repository ericrisco/rsc-harness (70 stars, last pushed today), licensed MIT. It adds 86 tokens to every session and 2,935 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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