Drop-in pandas replacement with ClickHouse performance. Use `import chdb.datastore as pd` (or `from datastore import DataStore`) and write standard pandas code — same API, 10-100x faster on large datasets. Supports 16+ data sources (MySQL, PostgreSQL, S3, MongoDB, ClickHouse, Iceberg, Delta Lake, etc.) and 10+ file formats (Parquet, CSV, JSON, Arrow, ORC, etc.) with cross-source joins. Use this skill when the user wants to analyze data with pandas-style syntax, speed up slow pandas code, query remote databases or cloud storage as DataFrames, or join data across different sources — even if they don't explicitly mention chdb or DataStore. Do NOT use for raw SQL queries, ClickHouse server administration, or non-Python languages.
72
90%
Does it follow best practices?
Run evals on this skill
Adds up to 20 points to the overall score
View guide
High
Do not use without reviewing
# 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 chdb1. "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 insteadfrom 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
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 SQL209 DataFrame methods supported. Full API → api-reference.md
from datastore import DataStore
customers = DataStore.from_mysql(host="db:3306", database="crm", table="customers", user="root", password="pass")
orders = DataStore.from_file("orders.parquet")
result = (orders
.join(customers, left_on="customer_id", right_on="id")
.groupby("country")
.agg({"amount": "sum", "rating": "mean"})
.sort_values("sum", ascending=False))
print(result)More join examples → examples.md
source = DataStore.from_mysql(host="db:3306", database="shop", table="orders", user="root", password="pass")
target = DataStore("file", path="summary.parquet", format="Parquet")
target.insert_into("category", "total", "count").select_from(
source.groupby("category").select("category", "sum(amount) AS total", "count() AS count")
).execute()| Problem | Fix |
|---|---|
ImportError: No module named 'chdb' | pip install chdb |
ImportError: cannot import 'DataStore' | Use from datastore import DataStore or from chdb.datastore import DataStore |
| Database connection timeout | Include port in host: host="db:3306" not host="db" |
| Join returns empty result | Check key types match (both int or both string); use .to_sql() to inspect |
| Unexpected results | Call ds.to_sql() to see the generated SQL and debug |
| Environment check | Run python scripts/verify_install.py (from skill directory) |
Note: This skill teaches how to use chdb DataStore. For raw SQL queries, use the
chdb-sqlskill. For contributing to chdb source code, see CLAUDE.md in the project root.
8d347f8
If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.