My_Idea_Is

A. WHAT IS RELATIONAL DATABASE MANAGEMENT SYSTEM?
ans: a database management system (DBMS) that is based on the relational model. Most popular commercial and open source databases currently in use are based on the relational model.

A short definition of an RDBMS may be a DBMS in which data is stored in the form of tables and the relationship among the data is also stored in the form of tables.

A relational database aims to achieve normalization of data. Normalization helps to reduce redundancy and update anomalies.

B. Define:

1. Key Fields
ans: A key field is a field or set of fields of a database (typically a relational database) table which together form a unique identifier for a database record (a table entry). The aggregate of these fields is usually referred to simply as "the key".

2. Database Records
ans: DB records contain two parts — a key and some data. Both the key and its corresponding data are encapsulated in DatabaseEntry class objects. Therefore, to access a DB record, you need two such objects, one for the key and one for the data.




3. Data Queries
ans: Data queries are not a replacement for data input methods.Instead they provide an easy way to query, or list data based upon an index, making the data easier to graph.

4. Data Types
ans: A data type (or data-type) is a set of values and the operations on those values.

5. Data Forms
ans: forms provide a quick and easy way to modify and insert records into your databases. They offer an intuitive, graphical environment easily navigated by anyone familiar with standard computer techniques.

6. Tables/Database Files
ans: file database describes any of various means to encode a database model (most commonly a table) as a plain text file.

7. Relationships
ans: Database relationships

Several types of relationships can be defined in a database. Consider the possible relationships between employees and departments.
One-to-many and many-to-one relationships

An employee can work in only one department; this relationship is single-valued for employees. On the other hand, one department can have many employees; this relationship is multi-valued for departments. The relationship between employees (single-valued) and departments (multi-valued) is a one-to-many relationship.

To define tables for each one-to-many and each many-to-one relationship:

1. Group all the relationships for which the "many" side of the relationship is the same entity.
2. Define a single table for all the relationships in the group.

Many-to-many relationships

A relationship that is multi-valued in both directions is a many-to-many relationship.

One-to-one relationships

One-to-one relationships are single-valued in both directions.