Added Residential and NonResidential entities to customer as subtype.

computer science

Description

1)  ERD Changes

1.      Removed Report entity

2.       Added Residential and NonResidential entities to customer as subtype.

3.      Added watermeter_id to Reading entity to provide a 1:N relationship

4.      Added meterreader_id to WaterMeter entity to provide a 1:N relationship

5.      Added reading_date to Reading entity and removed lastmeterread

6.      Added status to WaterMeter entity

7.      Added Account Entity

8.      Added serial number on water meter

 


 

2)  Data Dictionary

CUSTOMER

Attribute

Description

Required?

Not Null?

Key

Data type(size)

CustomerID

Unique ID for each customer

Yes

Ö

Primary

Varchar2 (7)

CustomerName

Customer’s Name

Yes

Ö

 

Char (100)

CustomerType

Customer’s Type

Yes

Ö

 

Char (30)

 

RESIDENTIAL

Attribute

Description

Required?

Not Null?

Key

Data type(size)

ResidentialID

Unique ID of residential

Yes

Ö

Primary

Varchar2 (7)

CustomerID

Unique ID of customer

Yes

Ö

Foreign

Varchar2 (7)

Address

Customer’s Address

Yes

Ö

 

Varchar2 (100)

 

NONRESIDENTIAL

Attribute

Description

Required?

Not Null?

Key

Data type(size)

NonresidentialID

Unique ID of non-residential

Yes

Ö

Primary

Varchar2 (7)

Customer_ID

Unique ID of customer

Yes

Ö

Foreign

Varchar2 (4)

Address

Customer’s Address

Yes

Ö

 

Varchar2 (100)

 

WATERMETER

Attribute

Description

Required?

Not Null?

Key

Data type(size)

WatermeterID

Unique ID assigned for each watermeter

Yes

Ö

Primary

Foreign

Varchar2 (10)

CustomerID

Unique ID of customer

Yes

Ö

Foreign

Varchar2 (7)

MeterreaderID

Meterreader who reads the watermeter

Yes

Ö

Foreign

Varchar2 (7)

WMAddress

Address of watermeter deployed

Yes

Ö

 

Varchar2 (100)

DeployedDate

Date watermeter deployed

Yes

Ö


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