RDBMS

RDBMS is Implementation of Relational database management system which is the first assignment on the course neural-symbolic.

It is a data base managment system that store structured data using tables(rows and columns);

Tables as Relations

A relational data model using n-ary relation to store data

R = {(a1,...,an) | a1 E A1 ,a2 E A2, ...,an E An}

where

• A table is a relation
• Rows are n-tuples
• Columns/Atributes comes from a defined set called Domain

Each attribute requires a uniqu identifier/name

Relational Schima and Relational instance

A relational Schima contains the table name and it's atribute name.

A relational instance is a set of finite tuples created with a predefined schema. Look at the example below,it is the relational schima where table name is student and Name,Age and Department are Attributes.

	Students
Name	Age	Department

Based on this relational Schima we can create a table that of students info.

Name	Age	Department
Kirubel	24	CompEng
Bemehiret	23	SoftEng
Debora	23	CompEng
Elias	25	ElecEng

Query Operations on RDBMS

We have six operations on the tables

1. Union : It is a relation between two tables where the resulting table will contain the information of both tables.

It is denoted by:

R1 U R2 = {(a1,...,an) | (a1,...,an) E R1 V (a1,..,an) E R1}

Note both the tables must have the same relational schema i.e. Attributes must match .

2. Intersection : It is a relation between two tables where the resulting table will contain information duplicated in both tables.

It is denoted by:

R1 n R2 = {(a1,...,an) | (a1,..,an) E R1 & (a1,..,an) E R2 }

Note both the tables must have the same relational schema ie. Attributes must match .

3. Difference : It is a relation between two tables where the resulting table will contain the information of the first table with out information in second table.

It is denoted by:

R1 - R2 = {(a1,...,an) | (a1,..,an) E R1 & ~((a1,..,an) E R2)}

Note both the tables must have the same relational schema ie. Attributes must match .

4. Projection

5. Selection

6. Natural join

Commands for the User Interface

The following commands are supported to use the RDBMS from command line

1. Create a relational schema with the specified name and attributes list

   create,rschema,<rschema name>,<list of column names>

   e.g: create,rschema,Student,Name,Age
   where Student is rschema name and Name,Age is list of column names.

2. Create an empty table with a given table name and table specification (i.e. relational schema)

   create,table,<table name>,<name of rschema>

   e.g: create,table,Attendance,Student
   where Attendance is the table name and Student is the name of the relational schema instance to use as specification for the table.

3. Insert a row into an existing table

   insert,<table name>,<row to insert>

   e.g: insert,Attendance,Kirub,25
   where Attendance is the table name to insert into and Kirub,25 is the data to be inserted into the Attendance table.

4. Display data stored in a table

   display,<table name>

   e.g: display,Attendance
   where Attendance is name of the table to be displayed.

5. Remove a row of data from a table

   remove,row,<table name>,<row to remove>

   e.g: remove,row,Attendance,Kirub,25
   where Attendance is name of the table and Kirub,25 is the data to be removed.

6. Remove or delete an existing table

   remove,table,<table name>

   e.g: remove,Attendance
   where Attendance is name of the table to be removed or deleted.

7. Union of two tables

   union,<first table name>,<second table name>

   e.g: union,Attendance,Grade
   where Attendance is name of the first table and Grade is name of the second table.

8. Intersection of two tables

   intersection,<first table name>,<second table name>

   e.g: intersection,Attendance,Grade
   where Attendance is name of the first table and Grade is name of the second table.

9. Difference of two tables

   difference,<first table name>,<second table name>

   e.g: difference,Attendance,Grade
   where Attendance is name of the first table and Grade is name of the second table

10. Projection of a table on to a list of attributes (i.e. columns)

    projection,<table name>,<list of column names>

    e.g: projection,Attendance,Name
    where Attendance is the table name and Name is columns list with single column names.

    More column names can be specified in the columns list

11. Select a row from a table with a given value for a column

    select,<table name>,<column name>,<value>

    e.g: select,Attendance,Age,25
    where Attendance is name of the table to select from, Age is the column used for selection and 25 is the value at the selection column.

12. Natural Join of the two tables

    Njoin,<first table name>,<second table name>

    e.g: Njoin,Attendance,Grade
    where Attendance is name of the first table and Grade is name of the second table.

13. Clear screen

    cls

14. Exit the program

    exit

Building and Installing

Perform the following steps at the shell prompt:

cd /to/project/root_dir
mkdir build
cd build
cmake ..
make -j
sudo make install