The document discusses features of object identity, the role of OIDs, value and type constructors, and provides examples of valid time tables, transaction time tables, and bitemporal tables. It also discusses creating tables with employee data and calculating salaries, and compares intelligent databases with temporal databases.

1. Assignment No. 2
Department: University Institute of Computing
Subject: Advanced Database Management
Systems
Subject Code: CAT-762
Session: Jan – April
Semester 4th
Submitting By: Submitted to
Kuldeep Kumar
UID: - 19MCA8202
Er. Sandeep Kaur
Group: - 6

2. 1. Write the features of object identity. What is the role of OID, Value,
and type constructors?
Features Of Object Identity:
• An object retains its identity even if some or all of the values of variables or
definitions of methods change over time.
• This concept of object identity is necessary in applications but doe not apply to
tuples of a relational database.
• Object identity is a stronger notion of identity than typically found in
programming languages or in data models not based on object orientation.
• Several forms of identity: value: A data value is used for identity (e.g., the
primary key of a tuple in a relational database).name: A user-supplied name is
used for identity (e.g., file name in a file system).built-in: A notion of identity
is built-into the data model or programming languages, and no user-supplied
identifier is required (e.g., in OO systems).
• Object identity is typically implemented via a unique, system-generated OID.
The value of the OID is not visible to the external user, but is used internally by
the system to identify each object uniquely and to create and manage inter-
object references.
Role Of OID, Value, and type constructors:
An object identifier is an extensively used identification mechanism jointly developed
by ITU-T and ISO/IEC for naming any type of object, concept or "thing" with a globally
unambiguous name which requires a persistent name. It is not intended to be used for
transient naming. OIDs, once allocated, should not be re-used for a different
object/thing. It is based on a hierarchical name structure based on the "OID tree". This
naming structure uses a sequence of names, of which the first name identifies a top-
level "node" in the OID tree, and the next provides further identification of arcs leading
to sub-nodes beneath the top-level, and so on to any depth. A critical feature of this
identification mechanism is that it makes OIDs available to a great many organizations
and specifications for their own use.
Default Constructor is also called as Empty Constructor which has no arguments and
It is Automatically called when we create the object of class but Remember name of
Constructor is same as name of class and Constructor never declared with the help of
Return Type. Means we can’t Declare a Constructor with the help of void Return Type.
if we never Pass or Declare any Arguments then this called as the Copy Constructors.
Parameterized Constructor is Another type Constructor which has some Arguments and
same name as class name but it uses some Arguments So For this, we have to create
object of Class by passing some Arguments at the time of creating object with the name
of class.
Copy Constructor is also Another type of Constructor. In this Constructor we pass the
object of class into the Another Object of Same Class. As name Suggests you Copy,
means Copy the values of one Object into another Object of Class.
Destructor As we know that Constructor is that which is used for Assigning Some
Values to data Members and For Assigning Some Values This May also used Some
Memory.

3. 2. A table consists of the following fields: -
Invoice Number Varchar2 4
Invoice Date Date
Customer Code Number 1
Product Code Number 1
Quantity Sold Number 3
There are ten customers with codes 0 to 9 and five products with codes 0 to 4. The
rates of products are Rs. 15, 35, 42, 51 and 60 respectively. Write a program to
find the total purchase in Rs. of each customer and total sale of each product using
this table and insert these values in two other tables.
Create table corder(“Invoice Number” varchar2(4),”Invoice Date” Date, “Customer
code” Number(1), “Product Code” Number(1), “Quantity Sold” Number(3));
insert into corder1 values('rj24','31-mar-12',2,0,3);
insert into corder1 values('rj24','31-mar-12',2,2,3);
insert into corder1 values('rj24','31-mar-12',2,3,3);
insert into corder1 values('rj24','31-mar-12',2,4,3);
insert into corder1 values('rj24','31-mar-12',2,5,3);
Create table totalpurchase(“Customer Code” Number(1), “Total Purchase” Number);
Create table totalsale(“Product Code” Number(1), “Total Sale” Number);
Create or replace procedure fint_sale_purchase as
Cursor c1 is
Select distinct (“Customer Code “)
From corder1;
Cursor c2(v_ccode number) is
Select*
From corder1
Where “Customer Code”=v_ccode;
Cursor c3 is
Select distinct(“product code”)
From corder1;
Cursor c4(v_pcode number)is
Select*
From corder1
Where “Product Code ”=v_pcode;
Rs number;

4. Total_purchase number:=0;
Total_sale number:=0;
Begin
Delete
From totalpurchase;
Delete
From totalsale
For i in c1 loop
For j in c2(i. “customer code”) loop
Select decode (j. “product code”,0,15,1,35,2,42,3,51,4,60,0) into rs from dual;
Rs: =rs*j. “quantity sold”;
Total_purchase: =total_purchase+rs;
End loop;
Insert into totalpurchase values (i. “customer code” ,total_purchase);
End loop;
Rs:=0;
For I in c3 loop
For j in c4(i. “product code”) loop
Select decode(j. “product code”, 0,15,1,35,2,42,3,51,4,60,0) into rs from dual;
Rs:=rs*j. “quantity sold”;
Total_sale:= total_sale+rs;
End loop;
Insert into totalsale values(i. “product code”, total_sale);
End loop;
End;
/
Output: -
exec find_sale_purchase;
select * from totalsale;
Product Code Total Sale
1 105
2 231
0 276
select * from totalpurchase;
Customer Code Total Purchase
2 276

5. 3. Discuss the following with suitable examples: -
a) Valid time table
b) Transaction time table
c) Bitemporal table
Valid time table: There are several ways to create a valid-time table:
Create a new table as a valid-time table
Add a valid-time column to a nontemporal or transaction-time table
Create a valid-time table from a copy of a nontemporal table
Example: To create a valid-time table, use a normal CREATE TABLE statement, and
define one column as a valid-time column. The valid-time column can either be derived
from two date, timestamp or timestamp with time zone columns, or can be a single
period data type column: PERIOD(DATE), PERIOD(TIMESTAMP[(n)]), or
PERIOD(TIMESTAMP[(n)] WITH TIME ZONE). Use the VALIDTIME or AS
VALIDTIME column attribute to assign the column to be the valid-time column.
Transaction time table: A transaction is an activity performed by entities within the
system. These activities are captured to represent events like item purchase, ticket
booking. Understanding transactions will give you clearer distinction of master tables
from transaction tables.
Example: For example, to describe a class of students all the information needed will
be part of master tables like student info, class info, teacher info, subject info. But to
know what daily attendance of the students will be captured in the transaction table.
Bitemporal table: As seen above, the temporal table allows for periods of time to be
stored in a database. This is ideal for showing state changes of objects (valid times).
Bitemporal design expands on this to model not only valid time, but to additionally
model transaction time. Transaction time represents the physical time at which a
transaction happened within the database.
Example: a shipment arriving at a warehouse. This could happen on Wednesday
(which would be the valid time that the shipment was in the warehouse). An operator
might update the system on the Thursday to state when the shipment arrived. The
moment they add the record to the system would be the transaction time. What this
allows us to determine at a later date is when that shipment was believed to be in the
warehouse, and also when that shipment was known to be in the warehouse according
to the database.

6. 4. Create a table EMPLOYEE with the following columns: -
Employee No. Varchar2 4
Employee Name Varchar2 30
Designation Varchar2 10
Category Character 1
Basic Salary Number 4
Category may be? J? ,?S?, or ?W? for Jr. officers, Sr. officers or Worker category.
Formulae: -
DA = 35% of Basic Salary correct up to paise.
HRA = 15% of Basic Salary subject to a maximum of Rs. 250/1000/30000 for
categories W/J/S
respectively.
Gross = Basic Salary +DA +HRA
Output the Employee Number and the Gross for each employee in a separate
table.
create table employee ("Employee No" Varchar2(4),"Employee Name" Varchar2(30),
Designation Varchar2(10), Category Character(1),"Basic Salary" Number(4));
Employee No Employee Name DESIGNATIO Category Basic Salary
1000 rakesh Sr.off j 3000
1001 kk Sr.off s 4000
1002 dk Jr.off w 5000
create table employee_gross;
create table gross("Employee No" Varchar2(4),"Gross Salary" Number(4));
create or replace procedure gross as
cursor c1 is
select * from employee;
emp_record employee%rowtype;
da number(20,2);
hra number(20,2);
gross number(20,2);
begin
delete
from employee_gross;
for emp_record in c1 loop
da:=emp_record."basic salary "*35/100;
hra: =emp_record."basic salary "*15/100;
if emp_record.category='j' and hra>250
then
hra: =250;
elsif emp_record.Category='s' and hra>1000
then
hra:=1000;
elsif emp_record.Category='w' and hra>30000
then
hra:=30000;
else
hra:=0;
end if;
gross:=emp_record."basic salary "+da+hra;
insert into employee_gross values(emp_record."Employee No ",gross);
end loop;
end;
/

7. 5. Compare and contrast the advantages and disadvantages of intelligent
databases with temporal databases.
Intelligent Database:
An intelligent database is a full-text database that employs artificial intelligence (AI),
interacting with users to ensure that returned items (hits) contain the most relevant
information possible. This is in contrast to a traditional database, which is searchable
only by keywords and verbatim phrases connected by Boolean operations such as AND,
OR, and NOT. Intelligent database technology is in its infancy, and is evolving as AI
becomes more advanced.
Temporal Database:
A temporal database is generally understood as a database capable of supporting storage
and reasoning of time-based data. For example, medical applications may be able to
benefit from temporal database support” a record of a patient's medical history has little
value unless the test results, e.g. the temperatures, are associated to the times at which
they are valid, since we may wish to do reasoning about the periods in time in which
the patients temperature changed.
advantage and disadvantage of intelligent database or temporal database:
Many companies offer products whose prices vary over time. Daytime telephone calls,
for example, are usually more expensive than evening or weekend calls. Travel agents,
airlines or ferry companies distinguish between high and low seasons. Sports centres
offer squash or tennis courts at cheaper rate during the day. Hence, prices are time
dependent in these examples. They are typically summarised in tables with prices
associated with a time period. As well as the user of a database recording when certain
data values are valid, we may wish to store (for backup, or analysis reasons) historical
records of changes made to the database. So each time a change to a database is made
the system may automatically store a transaction timestamp.
When a search is conducted using a traditional full-text database, the mere presence of
keywords and phrases in a referenced file does not guarantee that the contents of that
file will be relevant in a given context. An intelligent database provides expanded and
more flexible options for conducting queries. For example, a user might type in a
question as a full sentence. The database then provides a list of hits arranged according
to the likelihood that the resulting data contains a useful answer to that question. The
AI may correct suspected errors input by the user. Some intelligent databases display
synonyms or antonyms for keywords and phrases.