1. What is database?
A prearranged collection of figures known as data is called database.
2. What is DBMS?
It is a collection of programs that enables user to create and maintain a Database.
3. What is a Database system?
The database and DBMS software together is called as Database system.
4. What is RDBMS ?
RDBMS are database management systems that maintain data records and indices in tables.
5. What are the advantages of DBMS?
Redundancy is controlled.
Unauthorised access is restricted.
Providing multiple user interfaces.
Enforcing integrity constraints.
Providing backup and recovery.
6. What are the disadvantage in File Processing System?
Data redundancy and inconsistency.
Difficult in accessing data.
Data isolation.
Data integrity.
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1. Data redundancy and inconsistency
2. Difficulty in accessing data
3. Data isolation – multiple files and formats
4. Integrity problems
5. Atomicity of updates
6. Concurrent access by multiple users
7. Security problems
16. Define the "integrity rules"?
There are two Integrity rules.
Entity Integrity: States that "Primary key cannot have NULL value"
Referential Integrity: States that "Foreign Key can be either a NULL value or should be Primary Key value of other relation.
17. What are super, primary, candidate and foreign keys?
A superkey is a set of attributes of a relation schema upon which all attributes of the schema are functionally dependent. No two rows can have the same value of super key attributes.
A Candidate key is minimal superkey, i.e., no proper subset of Candidate key attributes can be a superkey.
A Primary Key is one of the candidate keys. One of the candidate keys is selected as most important and becomes the primary key. There cannot be more that one primary keys in a table.
Foreign key is a field (or collection of fields) in one table that uniquely identifies a row of another
problem and it will be used in this case to build the databases. The databases
- Trait like model represents one factor, meaning that each relationship will display the same attachment
These are covered briefly in appendices in the text. The relational model was first proposed by E.F. Codd in 1970 and the first such systems were developed in 1970s. The relational model is now the dominant model for commercial data processing applications. The relational model can be used in both conceptual and logical database design. The basic structure in the model is a table .Tables consists of rows and columns. Relationships in the relational model are represented implicitly through common attributes between different relations.
As defined by Kroenke Database is an integrated, self-describing collection of related data. Data is stored in a uniform way, typically all in one place- for example, a single physical computer. A database maintains a description of the data it contains and the data has some relationship to other data in the databa...
This will allow for data to be analyzed and placed on a separate non-operational database. Essentially this will be synced version of the operational database and will provide a centralized view of the main database. This could also be used as a backup to the original database.
From the scenario described above, I have determined that the following main entities are the most appropriate for a relational database: cemeteries, burial plots, burial records, monuments, buildings, and inscriptions. Each main entity and its significant attributes will be described below; however, a full list of attributes can be found in the appendix.
For example, a database may contain an employee table that has an emp_no column and an identification_no column. A data dictionary can explain that the emp_no column is an integer value containing the employee number assigned by the system. When a new employee is added to the system, a next number value is retrieved from a next number table and assigned to the new employee record. The data dictionary would also explain that the identification_no column is an alpha-numeric value that contains the employee's social security number for US residents and for non-US residents contains the employee's country code followed by their work visa number.
A dispute about an international contract may have foreign elements and thus one or both of the parties may be foreign, or the making or performance of the contract, or its terms, may be connected with one or
Primary data means original data that has been collected specially for the purpose in mind. It means someone collected the data from the original source first hand. Data collected this ways is called primary data.
A database is a collection of data which is organized and easy for users to find data. Database can record massive amount of data, it can be use for business and organization’s purpose. Every organization should have database security to secure the information of the organization.
distinguishes a tie between people that will provide that interaction as well as keep the interaction consistent on a regular basis.
A database is a structured collection of data. Data refers to the characteristics of people, things, and events. Oracle stores each data item in its own field. For example, a person's first name, date of birth, and their postal code are each stored in separate fields. The name of a field usually reflects...
With the modernization of NoSQL and it’s adaptation to fix problems with old relational databases, it is able to store data in many different ways. There are five main database types for NoSQL: relational, key-value, document databases, column family stores and graph databases. Each of the four are unique in their own way and thus different systems and companies support different database types. A key-value database is described by Pramod Sadalage, in his article on
Determining the tables can be the trickiest step in the database – the reports you want to print, the forms you was to use, the questions you want answered – don’t necessarily provide clues about the structure of the tables that produce them.
In our world, people rely heavily on the power of technology every day. Kids are learning how to operate an iPad before they can even say their first word. School assignments have become virtual, making it possible to do anywhere in the world. We can receive information from across the world in less than a second with the touch of a button. Technology is a big part of our lives, and without it life just becomes a lot harder. Just like our phones have such an importance to us in our daily lives, database management systems are the same for businesses. Without this important software, it would be almost impossible for companies to complete simple daily tasks with such ease.