PostgreSQL clone

This repo was made in educational purposes. This is more adaptation than clone.

Features

SQL commands recreated with use of java classes

• create (database / table)
• insert data into table
• select ('where' is supported)
• order by (more like orderUsing(Comparator))
• union
• join
• group by

Data storage

Every table is stored in 'data' folder in root directory. Each table is named as following 'databaseName.tableName' and data is stored in files as serialized java Map<String, Object>. There is only one concurrent connection to each table, that means that concurrency isn't supported, and after opening connection equality of stored data type and data type used to open connection is checked.

Test coverage

100% method coverage

94% line coverage