Mini-SQL-Engine

A mini SQL engine to replicate MySQL functionalities

Excecuting Code

• Code has been developed and tested in Python3
• Additional Required Modules are listed in requirements.txt. Install them by the following command:-

user@linux:~/Mini-SQL-Engine$ pip3 install -r requirements.txt

• In the files directory, there is metadata.txt, which holds the schema for tables, along with the data for tables. Also, data of tables is listed in .csv, and it's structure is written in metadata.txt
• To include any new table, please refer to metadata.txt for the structure syntax.
• For the sake of simplicity, attributes are integers.
• Syntax for executing code:-

user@linux:~/Mini-SQL-Engine$ python3 engine.py <Query within quotes>
For Example:-
user@linux:~/Mini-SQL-Engine$ python3 engine.py "Select * from table1"

Supported Operations

• Select all records from one or more tables:
  • For Example:- Select * from table_name
• Aggregate functions: Simple aggregate functions on a single column
  • sum, average, max and min
  • For Example:-. Select max(col1) from table1
• Project Columns(could be any number of columns) from one or more tables:
  • For Example:- Select col1, col2 from table_name
• Select/project with distinct from one or more tables:
  • For Example:- Select distinct col1, col2 from table_name;
• Select with where from one or more tables:
  • For Example:- Select col1,col2 from table1,table2 where col1 = 10 AND col2 = 20
  • Conditional Operations supported are:- >,<.<=,>=,=
  • Also, you can only use at max two conditions in where for comparison
• Projection of one or more(including all the columns) from two tables with one join condition:
  • For Example:-Select * from table1, table2 where table1.col1=table2.col2
  • For Example:-Select col1, col2 from table1,table2 where table1.col1=table2.col2