RDBMS
Introduction To RDBMS
Introduction:
In this article, you will learn what RDBMS is and why we use this in SQL server.
RDBMS stands for Relational Data Base Management System. It is based on relational model, described by E.F.Codd. In the RDBMS, data is reserved in the form of rows and columns. The relations among the tables, using primary keys, foreign keys and indexes are also stored in the form of the table. Thus, RDBMS is generally used by the developers for the purpose of storing the complex and huge amount of data.
Of late, many trading and an open-source database functions are relational. RDBMS is the basis for SQL and for all the latest database systems like MS SQL Server, Oracle, MySQL and Microsoft Access.
What is a Table
A table is a collection of the data elements and classified grouping of the fields (rows and columns).Table is the most clean form of the data storage. A table can have duplex types, while a true relation cannot have the duplex types.
Tables may save almost fixed data or may be regularly updated. Tables are also called the datasheets.
|
ID |
NAME |
AGE |
|---|---|---|
|
1 |
Avi |
15 |
|
2 |
Ashu |
22 |
What is field
Every table is busted up into a smaller item called fields. A field is a column in a table that is arrange to protect limited information about each record in the table.
The above employee table consist of four fields ID, NAME, AGE.
|
ID |
NAME |
AGE |
|---|
What is Row
A row is a collection of fields with in a table that are significant to a unique entity. A record is a horizontal entity in a table.
|
1 |
Avi |
15 |
What is column
A Column consist of all report associated with a particular fields in a table. It is a collection of data values. A column is a vertical entity in a table.
|
NAME |
|---|
|
Avi |
|
Ashu |
What is NULL value
A NULL value is a value in a field that present to be blank. If a column in a table is optional, we can insert a new data or create correction in a current record without adding a value to this column. NULL is used as a space for new or unused data. It is very necessary to know that a NULL value is totally different than a zero value or a field that contains spaces.
Summary:
Thus, we learned that RDBMS stored data in the form of rows and column and it sorts the huge amount of data.
