CLI Reference

loq provides a command-line interface compatible with Microsoft Log Parser 2.2.

Basic Syntax

loq [options] "SQL_QUERY"
loq [options] file:query.sql

Quick Examples

# Basic query
loq "SELECT * FROM data.csv"

# With input format
loq -i:JSON "SELECT * FROM data.json"

# With output format
loq -o:JSON "SELECT * FROM data.csv"

# Output to file
loq -o:CSV --ofile:output.csv "SELECT * FROM data.csv"

# Query from file
loq file:query.sql

Help

loq --help
loq --version

Input Options

Option	Description	Example
-i:FORMAT	Input format	-i:CSV, -i:JSON, -i:W3C
-iSeparator:SEP	Input field separator	`-iSeparator:"
-iHeaderRow:N	Header row number	-iHeaderRow:2
-iCodepage:CP	Input encoding	-iCodepage:UTF8
-recurse:N	Recursive depth	-recurse:3, -recurse:-1 (unlimited)
-iw:ON/OFF	Input wildcard mode	-iw:ON

Output Options

Option	Description	Example
-o:FORMAT	Output format	-o:CSV, -o:JSON, -o:SQLITE
--ofile:PATH	Output file path	--ofile:output.csv
--otable:NAME	Database table name	--otable:results
-oSeparator:SEP	Output field separator	`-oSeparator:"
-oCodepage:CP	Output encoding	-oCodepage:UTF8
-headers:ON/OFF	Include header row	-headers:OFF

Query Options

Option	Description	Example
file:PATH	Load query from file	file:query.sql
-q:ON/OFF	Quiet mode	-q:ON
-stats:ON/OFF	Show statistics	-stats:ON

Chart Options

Option	Description	Example
-chartType:TYPE	Chart type	-chartType:Bar, -chartType:Line, -chartType:Pie
-chartTitle:TITLE	Chart title	-chartTitle:"My Chart"

Streaming Options

Option	Description	Example
--follow	Follow mode (tail -f style)	--follow

Cloud Options

Option	Description	Example
--log-group:NAME	CloudWatch log group	--log-group:/app/logs
--log-stream:NAME	CloudWatch log stream	--log-stream:my-stream

Examples by Category

Basic Queries

# Select all
loq "SELECT * FROM data.csv"

# Select columns
loq "SELECT name, age FROM users.csv"

# Filter
loq "SELECT * FROM users.csv WHERE age > 30"

# Sort and limit
loq "SELECT * FROM users.csv ORDER BY age DESC LIMIT 10"

Input Formats

# CSV (default)
loq "SELECT * FROM data.csv"

# JSON
loq -i:JSON "SELECT * FROM data.json"

# W3C logs
loq -i:W3C "SELECT * FROM access.log"

# Filesystem
loq -i:FS "SELECT * FROM '/var/log'"

# EVTX
loq -i:EVTX "SELECT * FROM System.evtx"

# S3
loq -i:S3 "SELECT * FROM 's3://bucket/key.csv'"

Output Formats

# JSON output
loq -o:JSON "SELECT * FROM data.csv"

# Table output
loq -o:DATAGRID "SELECT * FROM data.csv"

# SQLite
loq -o:SQLITE --ofile:output.db "SELECT * FROM data.csv"

# Chart
loq -o:CHART -chartType:Bar --ofile:chart.png \
          "SELECT status, COUNT(*) FROM logs.csv GROUP BY status"

File Operations

# Output to file
loq -o:CSV --ofile:results.csv "SELECT * FROM data.csv"

# Query from file
cat > query.sql << 'EOF'
SELECT name, age
FROM users.csv
WHERE age > 30
ORDER BY age DESC
EOF
loq file:query.sql

# Multiple files with wildcards
loq "SELECT * FROM 'logs/*.csv'"

# Recursive
loq -recurse:3 "SELECT * FROM 'logs/*.log'"

Aggregation

# Count
loq "SELECT COUNT(*) FROM data.csv"

# Group by
loq "SELECT status, COUNT(*) FROM logs.csv GROUP BY status"

# Multiple aggregates
loq "SELECT category, COUNT(*), SUM(amount), AVG(amount)
           FROM sales.csv
           GROUP BY category"

JOINs

# Inner join
loq "SELECT u.name, o.total
           FROM users.csv u
           JOIN orders.csv o ON u.id = o.user_id"

# Left join
loq "SELECT u.name, COALESCE(o.total, 0) as total
           FROM users.csv u
           LEFT JOIN orders.csv o ON u.id = o.user_id"

Window Functions

# Ranking
loq "SELECT name, salary,
                  RANK() OVER (ORDER BY salary DESC) as rank
           FROM employees.csv"

# Partitioned ranking
loq "SELECT name, dept, salary,
                  ROW_NUMBER() OVER (PARTITION BY dept ORDER BY salary DESC) as dept_rank
           FROM employees.csv"

Streaming Mode

# Follow log file
loq --follow "SELECT * FROM '/var/log/app.log' WHERE level = 'error'"

Environment Variables

Variable	Description
AWS_ACCESS_KEY_ID	AWS access key
AWS_SECRET_ACCESS_KEY	AWS secret key
AWS_REGION	AWS region
AWS_PROFILE	AWS profile name

Exit Codes

Code	Meaning
0	Success
1	General error
2	Parse error (invalid SQL)
3	Execution error
4	File not found

Combining with Unix Tools

# Pipe to grep
loq -o:CSV "SELECT * FROM logs.csv" | grep error

# Pipe to jq
loq -o:JSON "SELECT * FROM data.csv" | jq '.name'

# Count results
loq -o:CSV -headers:OFF "SELECT * FROM data.csv" | wc -l

# Sort externally
loq -o:CSV -headers:OFF "SELECT * FROM data.csv" | sort -t',' -k2

Performance Tips

# Select only needed columns
loq "SELECT id, name FROM huge.csv"  # faster than SELECT *

# Use LIMIT for exploration
loq "SELECT * FROM huge.csv LIMIT 100"

# Filter early
loq "SELECT * FROM huge.csv WHERE status = 'active'"

See Also

• CLI Options - Detailed option reference
• Input Formats
• Output Formats