README.md

Database-System-Implementation

A single user database management system in C++, that supports SQL operations like Select, Project, Join and Group By.

Project Milestones

Project 1 : Implementing Heap File
Project 2 : Sort the records
Project 3 : Implementing Relational Operators
Project 4 : Query Compilation and Optimization

Installation and Execution

Installation

Step 1 : Download code

Download code files into a folder

Step 2 : Install TPC-H Data files Generator

mkdir ~/datafilesgit
cd datafilesgit 
git clone https://github.com/electrum/tpch-dbgen.git
make

To generate data files (.tlb) Generate 10MB data

./dbgen -s 0.01

Generate 1GB data

./dbgen -s 1

This will generate 8 *.tbl files containing the data in CSV format with | separator
Copy these files into the required folder destination Refer folder structure

Step 3 : Set path

Open file "test.h" and set path in below lines

const char *dbfile_dir = "./db_files/"; // dir where binary heap files should be stored
const char *tpch_dir ="./data_files/"; // dir where dbgen tpch files (extension *.tbl) can be found
const char *catalog_path = "catalog"; // full path of the catalog file

Step 4 : Verify Folder structure

|-Database-System-Implementation
    |- code files #(.y , .c)    # Downloaded code files 
    |- header_files             # Downloaded code files 
        |- *.h files
    |- src                      # Downloaded code files 
        |- *.cc files
    |- data_files               # (copy t-pch generated files in this folder)
        |- *.tlb files
    |- db_files                 # Create folder 
        |- *.bin files          # (created when tlb files are loaded into the system)

Execution

Compile

make -Bf Makefile
make -Bf MakeFile main

Run

./test.out

Run all test cases given in testcases.txt

./testscript.sh

Implementation

How is the data stored in the system?

Data imported from tlb file is stored in a DBFile object. The structure of the DB file is given below. The file type is .bin

Each record extract from the tlb file is encoded in binary and stored as the following structure. Each record is of variable size.