BitMatrix

BitMatrix is a Java-based relational database management system. It provides functionalities for creating tables with defined schemas, inserting, deleting, and looking up data. The system supports both in-memory and file-backed tables, along with indexing for faster data retrieval.

Project Structure

BitMatrix_extracted/
└── BitMatrix
    ├── .mvn
    │   └── wrapper
    │       └── maven-wrapper.properties
    ├── src
    │   ├── main
    │   │   └── java
    │   │       └── bitmatrix
    │   │           ├── resource
    │   │           │   ├── AndCondition.java
    │   │           │   ├── Condition.java
    │   │           │   ├── EqCondition.java
    │   │           │   ├── OrCondition.java
    │   │           │   └── SelectQuery.java
    │   │           ├── BitMap.java
    │   │           ├── BlockedFile.java
    │   │           ├── Constants.java
    │   │           ├── Index.java
    │   │           ├── ITable.java
    │   │           ├── IType.java
    │   │           ├── MainApplication.java
    │   │           ├── OrderedIndex.java
    │   │           ├── Schema.java
    │   │           ├── Table.java
    │   │           ├── TableHeap.java
    │   │           ├── Tuple.java
    │   │           ├── TypeInt.java
    │   │           └── TypeVarchar.java
    │   └── test
    │       └── java
    │           └── bitmatrix
    │               ├── IndexPerformance.java
    │               ├── IndexTableTest.java
    │               ├── IndexTest.java
    │               ├── JoinTest.java
    │               ├── ManyRowsTest.java
    │               ├── QueryTest.java
    │               ├── TableHeapTest.java
    │               ├── TableTest.java
    │               └── TupleTest.java
    ├── insertMany
    ├── mvnw
    ├── mvnw.cmd
    ├── pom.xml
    ├── rows1000
    └── test.db

Build & Run

This project is built using Apache Maven.

Prerequisites

• Java Development Kit (JDK) version 17 or later.

• Build system: Maven (optional)

Option A: Compile with javac (no build tool)

# from repo root
find . -name "*.java" > sources.txt
mkdir -p out
javac -d out @sources.txt
# run a main class (if present)
java -cp out bitmatrix.MainApplication

Option B: Maven

To build the project and run the tests, execute the following command in the root directory:

./mvnw clean install

Running the Application

The MainApplication class provides a simple demonstration of the database's features. To run it, execute the following command after building the project:

java -cp target/classes bitmatrix.MainApplication

Usage

This library provides a bit-matrix (boolean matrix backed by bits) with typical operations:

• Set/clear/get bits
• Row/column operations
• Logical operations (AND/OR/XOR)
• Transpose, population count, serialization

Explore classes under src/ for the API (e.g., BitMatrix, BitVector, and utilities).

Features

• Schema Definition: Create tables with a defined schema, specifying column names, data types (integer and varchar), and primary keys.
• Data Manipulation: Insert, delete, and look up data in tables.
• In-Memory and File-Backed Tables: Choose between Table for in-memory operations and TableHeap for file-backed storage.
• Indexing: Create indexes on integer columns to speed up data retrieval.
• Querying: Perform select queries with conditions (e.g., equality, AND, OR) and projections.
• Natural Joins: Join tables based on common column names.

Testing

The project includes a comprehensive suite of JUnit tests to ensure the correctness of the database's functionality. The tests cover various aspects of the system, including:

• Tuple and schema creation.
• Data insertion, deletion, and lookup.
• Indexing.
• Querying with different conditions.
• Table joins.

Packages

• bitmatrix
• bitmatrix.resource