chDB is an in-process OLAP SQL engine powered by ClickHouse, allowing applications to query analytical data without running a separate database server. Python users and data practitioners use it to work with formats such as Parquet, CSV, JSON, Arrow, and ORC through SQL or a pandas-compatible API. Its catalogue add-ons provide agent instructions, rules, skills, and an agent for working with the project.
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.
npx skills add chdb-io/chdb --skill chdb-datastoregit clone --depth 1 https://github.com/chdb-io/chdbWrote 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.
[](https://agentmods.dev/skills/chdb-io/chdb/chdb-datastore)<a href="https://agentmods.dev/skills/chdb-io/chdb/chdb-datastore"><img src="https://agentmods.dev/badge/skills/chdb-io/chdb/chdb-datastore/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/chdb-io/chdb/chdb-datastore"><img src="https://agentmods.dev/badge/skills/chdb-io/chdb/chdb-datastore.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00168 | $0.01372 |
| Opus 5.5 | $0.00067 | $0.00549 |
| Sonnet 5.5 | $0.00034 | $0.00274 |
| Haiku 4.5 | $0.00017 | $0.00137 |
Grade A, and why
chdb-datastore 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 1mo ago.
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.
Copies of this mod
2 near-identical copies found in the catalogue:
- chdb-datastore — 92% identical, 3 lines differ
- chdb-datastore — 89% identical, 4 lines differ
How it starts
The opening of the file, as written. The whole thing — 147 lines — stays where its author put it; the contents beside it link to each section on GitHub.
chdb DataStore — It's Just Faster Pandas
The Key Insight
# Change this:
import pandas as pd
# To this:
import chdb.datastore as pd
# Everything else stays the same.
DataStore is a lazy, ClickHouse-backed pandas replacement. Your existing pandas code works unchanged — but operations compile to optimized SQL and execute only when results are needed (e.g., print(), len(), iteration).
pip install chdb
Decision Tree: Pick the Right Approach
1. "I have a file/database and want to analyze it with pandas"
→ DataStore.from_file() / from_mysql() / from_s3() etc.
→ See references/connectors.md
2. "I need to join data from different sources"
→ Create DataStores from each source, use .join()
→ See examples/examples.md #3-5
3. "My pandas code is too slow"
→ import chdb.datastore as pd — change one line, keep the rest
4. "I need raw SQL queries"
→ Use the chdb-sql skill instead
Connect to Any Data Source — One Pattern
from datastore import DataStore
# Local file (auto-detects .parquet, .csv, .json, .arrow, .orc, .avro, .tsv, .xml)
ds = DataStore.from_file("sales.parquet")
# Database
ds = DataStore.from_mysql(host="db:3306", database="shop", table="orders", user="root", password="pass")
# Cloud storage
ds = DataStore.from_s3("s3://bucket/data.parquet", nosign=True)
# URI shorthand — auto-detects source type
ds = DataStore.uri("mysql://root:pass@db:3306/shop/orders")
All 16+ sources and URI schemes → connectors.md
After Connecting — Full Pandas API
result = ds[ds["age"] > 25] # filter
result = ds[["name", "city"]] # select columns
result = ds.sort_values("revenue", ascending=False) # sort
result = ds.groupby("dept")["salary"].mean() # groupby
result = ds.assign(margin=lambda x: x["profit"] / x["revenue"]) # computed column
ds["name"].str.upper() # string accessor
ds["date"].dt.year # datetime accessor
result = ds1.join(ds2, on="id") # join
result = ds.head(10) # preview
print(ds.to_sql()) # see generated SQL
What ships with it
4 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.
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.
- 1mo ago First seen · 147 lines · 168 tokens per session scan A 7f991abbd7a2
chdb-datastore is a skill published in the GitHub repository chdb-io/chdb (2,920 stars, last pushed 8d ago), licensed Apache-2.0. It adds 168 tokens to every session and 1,372 once invoked, about $0.0007 per session on Opus 5.5. 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.
Other skills, from other repositories
duckdb
Use when analytical SQL must run in-process with no server: Parquet/CSV/JSON/Arrow queried in place, OLAP embedded in an app or notebook, a slow pandas groupby on multi-GB data, or S3/lakehouse data read without downloading. NOT a multi-user analytics server (that is clickhouse-analytics), NOT an app's transactional…
knowledge_graph_skill
Skill for searching and evolving the SQLite-backed Knowledge Graph. Use this when you need structured fact/concept/link search across one or more teams, NPCs, or directory scopes. The Knowledge Graph (KG) is stored in the application's database (not YAML). It is scoped by (teamname, npcname, directorypath). Facts and…
clickhouse-analytics
Use when running a ClickHouse server for high-volume OLAP: choosing a MergeTree engine and ORDER BY/PARTITION BY keys, ingesting billions of event/log/metric rows, pre-aggregating with materialized views, or fixing a query that scans instead of pruning. NOT in-process file analytics (that is duckdb), NOT OLTP CRUD…
data-science-analytics-engineering
Use this skill when asked about analytics engineering, dbt, data modeling, metrics layer, semantic layer, Cube.js, MetricFlow, dbt metrics, SQL analytics, window functions, CTEs, pivot/unpivot, data modeling for analytics, OBT, dimensional modeling, medallion architecture, bronze/silver/gold, or analytical SQL. This…
duckdb
Run embedded OLAP SQL on Parquet/CSV locally; configure memory and thread limits; attach remote files safely; export with COPY; avoid multi-writer locks and treating DuckDB as a production server database.
database-expert
Act as a database expert using the Database Operations MCP tools (connections, schema, query, export).