Data definition language, Database Management System

Assignment Help:

Data Definition Language

It organises the data in the form of columns and rows. But what does the data field column of table accumulate? How do you describe it using SQL?

The Data definition language (DDL) defines a set of commands used in the modification and creation of schema objects such as indexes, tables, views etc. These commands give the ability to create, drop and alter these objects. These commands are linked to the management and administrations of the databases. Before and after every DDL statement, the current transactions are implicitly committed, that is changes made by these commands are permanently stored in the databases. Let us talk about these commands in more detail:

CREATE TABLE Command

Syntax:

CREATE TABLE

(

Column_name1 data type (column width) [constraints], Column_name2 data type (column width) [constraints], Column_name3 data type (column width) [constraints],

...............................................

);

Where table name assigns the name of the table, column name describes the name of the field, data type specifies the data type for the field and column width distribute specified size to the field.

 

 

 


Related Discussions:- Data definition language

Functional dependencies, CAR SALE (Car_id, Option_type, Option_listprice, S...

CAR SALE (Car_id, Option_type, Option_listprice, Sale_date, Option_discountedprice) This relation refers to options installed in cars (e.g., cruise control) that were sold at a de

Related fields in a database are grouped in which form, Related fields in a...

Related fields in a database are grouped in which form? Related data fields in a database are grouped to form a data record. (A record is a collection of related fields)

How does query tree represent relational algebra expression, How does a que...

How does a query tree represent a relational algebra expression?  Discuss any three rules for query optimisation, giving example as to when should each rule be applied.     Ans

What is the highest normal form of the table - normalization, In problems 1...

In problems 1 - 4, you are given the columns of a table, and a set of functional dependencies.  Determine the normal form of this table.  Remember that the normal form is the HIGHE

Enumerate about the high-level transitions result, Show, with the help of a...

Show, with the help of an example, that relatively high-level transitions result when system or program is stimulated by the outside events. In diagram below, we can observe i

Explain the functions and components of ddbms, Question 1 Explain the conc...

Question 1 Explain the concept of database recovery management. Explain the different levels of backup used for recovering data Question 2 What are the different types of par

Relationships, Let us first describe the term relationships. What Are Re...

Let us first describe the term relationships. What Are Relationships? A relationship can be defined as: A set of associations or connection, or A rule for communic

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd