Query

A lightweight SQL-like query engine for CSV files, built in C++ as a learning project.

Features

• Filter rows with comparison operators (==, >, <)
• Select specific columns
• Sort results by any column (numeric or string)
• Pretty-printed table output

Building

Requires a C++23 compiler (GCC 13+ or Clang 16+). Includes a Makefile. You can just do make.

make clean && make

Binary outputs to /build/query

Usage

./build/query --select col1 col2 col3 --where column --operation ">" -v value --sort column

Operation can be <, >, or ==.

Example:

./build/query --select species petal_width petal_length --where petal_length --operation ">" -v 6.0 --sort petal_width 

This would output:

Limitations

• Single CSV schema (hardcoded for iris.csv structure)
• No JOIN, GROUP BY, or aggregate functions
• Single condition filtering only (no AND/OR)

Dependencies

Included as vendored headers (no installation needed):

• CSV Parser by Ben Strasser
• CLI11