Example of sequences, Database Management System

Assignment Help:

Example: Create a sequence named SEQSS that starts at 105, has a step of 1 and can take maximum value as 2000.

 CREATE SEQUENCE SEQSS START WITH 105

INCREMENT BY 1

MAX VALUE 2000;

How the sequence so formed is used? The following sequence of commands try to illustrate the use of the sequence SEQSS.

Suppose a table person exists as: SELECT * FROM PERSON;

Output:             CODE      NAME         ADDRESS

------                      -------    --------         ---------------

                               104       RAMESH    MUMBAI

Now, if we give the command:

INSERT INTO PERSON

VALUES (SEQSS.NEXTVAL, &NAME, &ADDRESS) 

On implementation of statement above do the following input:

Enter value for name: 'Rakhi'

Enter value for address: 'New Delhi'

Now, here is the following command to see the output:

SELECT * FROM PERSON;

CODE        NAME           ADDRESS

--------- --------------- -----------------

104        RAMESH         MUMBAI

105        Rakhi             NEW DELHI

 

The explanations of sequences such as minimum value, maximum value, increment or step are stored in the data dictionary.  For instance, in oracle it is stored in the table user_sequences. You can see the explanation of sequences by giving the SELECT command.


Related Discussions:- Example of sequences

Maping constraits, #question.what is mapping constraints and types?.

#question.what is mapping constraints and types?.

Which operator is cartesian product in relational algebra, Which operator i...

Which operator is Cartesian product in relational algebra? Cartesian product in relational algebra is a binary operator. (It requires two operands. e.g., P X Q)

Draw an er diagram with primary key for a farm, Draw an ER diagram that rep...

Draw an ER diagram that represents the information described below. Show all entity sets, relationship sets, primary keys, and the mapping cardinality of the relationship sets.

Hierarchical model is also known by, Hierarchical model is also known by? ...

Hierarchical model is also known by? A hierarchical model is also known as a Tree structure.

What is the difference between a key and a superkey, What is the difference...

What is the difference between a key and a superkey? Key - A key a single attribute or a combination of two or more attributes of an entity set which is used to identify one

Explain the concept of a data model, Explain the concept of a data model ? ...

Explain the concept of a data model ? Data Model - Model is an abstraction procedure which hides irrelevant details although highlighting details relevant to the application

Explain heap file with advantages, Explain heap file with advantages? H...

Explain heap file with advantages? Heap File is an unordered set or a group of records, stored on a set of pages. This class gives basic support for inserting, updating, select

What does data dictionary is a special file contains, What does data dictio...

What does data dictionary is a special file contains ? The data dictionary is a special file contain The name of all fields in all files.The width of all fields in all files an

Which operator is used to compare a value to a list literals, Which operato...

Which operator is used to compare a value to a list of literals values that have been specified? BETWEEN operator is used to compare a value to a list of literals values that h

Explain the timestamp ordering protocol, Timestamp Ordering Protocol A ...

Timestamp Ordering Protocol A timestamp is a tag that can be attached to any transaction or any data item, which indicates a specific time on which the transaction or data item

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