| name | dataql-quick |
| description | Quick data queries and previews. Use when user wants to see contents of a data file, check schema, or do simple filtering on CSV, JSON, or other data files. |
| tools | ["Bash"] |
DataQL Quick Query
For fast data inspection and simple queries using DataQL.
Quick Commands
| Task | Command |
|---|
| Preview file | dataql run -f <file> -q "SELECT * FROM <table> LIMIT 5" |
| Count rows | dataql run -f <file> -q "SELECT COUNT(*) FROM <table>" |
| Check schema | dataql run -f <file> -q ".schema <table>" |
| List tables | dataql run -f <file> -q ".tables" |
| Distinct values | dataql run -f <file> -q "SELECT DISTINCT <column> FROM <table>" |
| Filter rows | dataql run -f <file> -q "SELECT * FROM <table> WHERE <condition> LIMIT 10" |
File Naming Convention
- Table name = filename without extension
users.csv -> table name is usersorders.json -> table name is ordersdata.parquet -> table name is data
Examples
Preview a CSV file
dataql run -f users.csv -q "SELECT * FROM users LIMIT 5"
Count records
dataql run -f orders.json -q "SELECT COUNT(*) as total FROM orders"
Check structure
dataql run -f data.parquet -q ".schema data"
Simple filter
dataql run -f products.csv -q "SELECT name, price FROM products WHERE price > 100 LIMIT 10"
Read from stdin
cat data.csv | dataql run -f - -q "SELECT * FROM stdin_data LIMIT 5"
Note: When reading from stdin, the default table name is stdin_data.
Supported Formats
- CSV (with custom delimiter:
-d ";")
- JSON (arrays or objects)
- JSONL/NDJSON
- XML
- YAML
- Parquet
- Excel (.xlsx, .xls)
- Avro
- ORC
Output Options
- Default: formatted table
- JSON output: pipe to
jq or use export
- CSV export:
-e output.csv -t csv
- JSONL export:
-e output.jsonl -t jsonl
Exploratory Statistics
dataql describe -f data.csv
dataql run -f data.csv -q ".describe data"
Quick Troubleshooting
| Problem | Solution |
|---|
| "column not found" | Check column names with .schema (case sensitive) |
| "table not found" | Table name = filename without extension |
| Too much output | Add LIMIT 10 or LIMIT 5 to query |
| File too large | Use --cache flag to cache imported data |
| Wrong delimiter | Use -d ";" for semicolon-separated files |
Notes
- Always use LIMIT for large files to avoid overwhelming output
- Use
.schema first to understand column names and types
- For stdin input with non-CSV format:
-i json or -i jsonl
- Use
--cache for repeated queries on the same file
- Use
-Q (quiet) to suppress progress bar in scripts
