Database Design

A row represents a record and a column represents a field.

An attribute is another name for a field in a table. Some attributes are used as keys to help specifically identify individual records,like a code number or reference number for example. Most attributes are not used as keys. Any of those are non-key attributes.

You would have a field of data in one table which has corresponding data in another. In at least one of the tables, depending on the type of relationship, a field would be the primary key. In the other table it would either also be the primary key or be a foreign key, meaning it is the primary key of a different table. The relationships are made by connecting the corresponding fields. They are not always copied as such. Although fields may be corresponding, it is possible to have data in one that is not in the other, though that data may be added later if needed. All relationships can be built before any data is entered into any of the tables. It is part of the design process of the database. All relationships should be defined before data goes in and even before the tables are actually created.

Phone numbers should always be stored in a text format and never as in a number field. There are several of reasons for this. You never do calculations with phone numbers; you may have a zero at the start of a phone number, which would disappear if left in a number format and you may, as in this case, have other characters in a phone number that are not digits, which would not be accepted in a number format.

no

A record identified by 2 or more fields is said to have a composite key.

Do you mean ...

One-To-Many

One-To-One

Many-To-Many

Many-To-One

Vic(S)

That's what's known as a simple transposition cipher.

Usually there is no use of nulls but in some case there might be some use. Like consider a case a persons address has been changed but the new address is not known. In this case it is prefer to left the field null instead of wrong address.

Prior to the use of DBMS Traditional file processing system were in use . These were the system that are used as database that time. These system do not supports the query.

No, a primary key do not refers to the whole table .A primary key refers to a field in the table that is not null and unique.

Two advantages of using a database over paper are increased data security through user access control and faster data retrieval through querying capabilities. Additionally, databases allow for easier data manipulation and organization compared to paper records.

The RDBMS (Relational Database Management System) is responsible for the control of the database however it requires appropriate planning and implementation of your design in order for this to work properly. Further proper maintenance of the Database environment is critical to its on-going operation. In short proper design by the database architect followed by proper implementation of this design by the DBA or SQL Developer coupled with proper SQL environment deployment is responsible for the healthy operation of a RDBMS.

A given field in a database table might be for a values that, in certain case, no such values exist or can be determined. For example, in an employee database, a field might be a foreign key to that employee's direct manager. However, in the case of the CEO, there is no such person. In that case, the field would be set to Null.

Yes it could. It would have a primary key for its own use and it could then have a foreign linking it to another table. If it is only linked to one other table, then it would only need one foreign key. It is also possible to have the same foreign key linking to more than one table.

A field that is not unique and null can not be used as a primary key. Praimary key must satisfy the conditions of not null and unique.

It refers to the connection between two tables. For example, in one table there may be personal details for employees, like name, address, date or birth etc. In another there may be could be payment details for those employees. Their personal details will not appear in that table. In each table there would be one common field, like an employee number. If you know the employee number from the personal details table or the wages table, you can check in the other table and find that number. The details with it relate to the particular person. So even though there name is not in the wages table, you can still find their details, by looking for their employee number. The connection of having an employee number in both tables that can be matched up is a relationship.

Database normalization, or data normalization, is a technique to organize the contents of the tables for transactional databases and data warehouses. Normalization is part of successful database design; without normalization, database systems can be inaccurate, slow, and inefficient, and they might not produce the data you expect.

foreign key

A report is a database object that allows you to organize, summarize, and present selected data from the database in a formatted way for printing or viewing. It provides a structured presentation of data that can be customized to meet specific reporting requirements.

One dimensional data storage is when you store a series of data in a linear way. An example of this would be an array, which stores data in a series, and access that data by indexing it. A linked list is another example of a data structure that behaves one dimensionaly.

Yes. Primary key can be inserted to one field in the database. The field should be unique and not null.

A database management system (DBMS) consists of several components. Each component plays very important role in the database management system environment. The major components of database management system are:

1. Software

2. Hardware

3. Data

4. Procedures

5. Database Access Language..

Typically, the DBA (database administrator) schedules and oversees backups as well as recoveries.

We explicitly choose a primary key.A primary key should satisfy the following conditions: 1) it should not be null 2) it should be unique.