The Basic Elements of a Database and DBMS
You can only achieve the arrangement of collected and gathered data using a database. A database is a well-arranged and organized collection of structured data and information stored in a computer.
The Database Management System (DBMS) monitors and controls a database. Data is a raw fact that has not been processed to give meaningful information. It includes age, class, tribe, telephone number, city, and streets.
Data are usually arranged in rows and columns on a table to ensure seamless processing. While recorded on a table, the data can be arranged, removed, and managed easily. Structured Query Language (SQL) is the mostly used programming language for data query and entry.
The different database types have several elements in common. This article covers the basic elements of database and database management (DBMS).
Elements of a Database
Database elements are the group of objects or entities that makes up a database. They include tables, indexes, data elements, database schemas, fields, columns, records, rows, keys, relationships, and data types.
The table is the simplest and primary unit of organization and storage of data in a database. You need this database element to modify and check for stored data.
When there is more than one table containing a database, they are always connected by what we call a relationship.
The relationship between the related tables makes it easy to link them together and figure out what they have in common. A table is a composition of related data items, usually with a unique identity.
A table is usually in rows (horizontal) and columns (vertical), all arranged physically in a grid model. Every row and column intersect at a point called a cell. Each cell contains data of unique identity as every data can only be accessed by their names.
The database table consists of four major types.
- Subset Tables comprise subsets of data obtained from a database table.
- Data Tables are the primary storage of data in a database.
- Join Tables help summon a link or relationship between tables, majorly two that might seem related.
- Validation Tables, also known as code tables, help to validate data entries from other tables. Tables make data easily accessible to users. However, some sets of delimits and constraints control the type of data allowed on the table.
A column, commonly called a field, is a particular type of data on a table. It is believed that a column only exists in a table, while an attribute exists in an entity.
On the contrary, attributes can be columns, and entities can form a table against the previous immediate claim when a business model transforms into a database model.
A column is the smallest storage element in any database and depicts related records of a table. A unique data type is given to every column. The data entered into the table will be dependent on the table's data types.
3. Database Schema
A database schema represents groups of related objects in a database. Some objects might be related to one another in a schema.
This database element gives access to just a single owner who has exclusive access to modify, reclassify and manipulate the makeup of objects found within a schema. It is always linked to a particular or unique user account in a database for specific purposes.
There are three models related to a schema.
The Conceptual Model
The conceptual model is otherwise known as the logical model. It is referred to as the fundamental model in a database.
A conceptual model is characterized by organizational and physical structures usually used to understand database structures like views, indexes, and constraints.
The Internal Model
The internal model is also known as the physical model. Just as its name implies, it majors on the physical storage in a database. Additionally, the internal model regulates access to data in a database.
Finally, it helps distinguish between the hardware's physical specifications and the OS (Operating System) initiated by the database model.
The External Model
The external model is commonly known as the application interface. With the application interface, users might be able to access schema in many ways, like the data input. It makes establishing a relationship between the database model and user application feasible.
A row is the collection of vertical records in a database. The population of rows in a table is not constant. A collection of data in a row is also known as a tuple.
5. Data Types
Data types control the type of data you can enter in a column. The following are the available data types:
- Numeric data types can only be used to store numeric values, that is, numbers.
- Alphanumeric data types consist of alphabetical characters, numerical values, and a combination of both. However, the alphanumeric data type only considers stored numeric data values as alphabetical characters, not numbers.
- Date and Time data types enable the storage of data and time. This data type varies with the Relational Database Management System (RDBMS) employed.
A key is an entity of a database that is used to identify or point out desired data in a table. This database element is usually most associated with just a single column and could be more than one column at times.
Hence, there are two main types of keys:
Primary Keys combine single or multiple-column values obtained from a table.
Moreover, a primary key will not allow duplicate entries even if the table does not have the fundamental identity of table values like SSN, school, and examination registration numbers that are unique.
These table values are never the same and can be set as a primary key in a database.
Foreign keys always have primary keys or keys as references in a different table. Primary keys are considered the mother table, while the foreign key is the child table. It helps to create a relationship between two tables.
There are various tables in a database that are related. A relational database is a modern database that creates links between tables using primary and foreign keys.
Entering data in a table and creating links between tables helps to reduce data redundancy in the relational database. There are three types of relationships in a table under the database elements.
- One-to-One Relationship relates one record with another in a different table.
- One-to-Many Relationship links one table record to more than one record from another table.
- Many-to-Many Relationships are more comprehensive than the first two. Here, many records are linked to records from a different table; consequently, you can connect more records in the second table to many more in the top table.
What is a Database System?
Database System or DBMS is the software that entails every process of gathering, collecting, storing, monitoring, and sorting similar information or data in the same criteria as a software program.
This system gathers logically similar data through the various Database Management System's software.
A database system requires an administrator known as the Database Administrator saddled with the responsibility of managing every activity of a database system. They include access regulation, backup actions, database security, and data recovery.
Data could be in any format in a database system. It can either be unstructured or structured, depending on the arrangement of the data.
When complex data such as the 3V's (volume, velocity, and variety) are combined, it might not be easy to process them because they are a group of structured and unstructured data.
However, due to the technological advancement of databases, you can easily process and analyze big data.
A standard database can keep and retrieve or revive data when lost. A relational model is a database with the specific function of processing and storing arranged or structured data.
Structured Query Language (SQL) is majorly used to access a series of data from database tables. DBMS and databases are key when analyzing and processing complex data. DBMS registered trademarks are Microsoft Access, Sybase, Oracle, dBase, and MY SQL.
Key Features of a Good Database System
1. Reduction of Data Redundancy and Duplication
Since many people have access to databases, the problem of repeating the same data set is big.
Database management helps to sort out the problem of redundancy since data are stored and arranged in a structured manner which will not accommodate redundancy and duplication.
Another thing to note is that database systems store every single piece of information uniquely; hence, multiple possibilities of data occurring are negligible.
Furthermore, due to the setup of database systems, a single data is made available to all end users, who can make changes while accessing the information.
Any alteration made by any user will affect the database file of every other user, thus lowering the chances of data redundancy and duplication.
2. Space Reduction and Economic Spending
Database management systems have many users accessing them. You can not avoid a large amount of data storage. With the help of adequate structuring and data integration, a lot of space is made available for the seamless functioning of the database system.
Many companies and organizations spend a lot on data security. Database systems will help them save money and space through proper data management.
3. Data Structuring and Arrangement
DBMS store data in a structured manner using the hierarchical database structure with many database elements, including tables, records, and others, to generate reports.
All the data entered into a database are organized in structures and stored so that updating and other changes can easily be done without issues.
4. Database Customization
You can make every database suit the end user's unique desire. Users can customize elements of a database, such as tables, rows, columns, records, and others, to meet the user's demands.
For example, large binary objects, known as BLOBS, enable storing images. You can implement the mappings in tables to sort complex data.
5. Data Extraction
Database management allows end users to extract their information. They can print, save and display the records however they like. However, only authorized user of a database has the advantage of accessing and extracting records from the database.
Unauthorized end users do not have access to the files in the database, thereby ensuring data security.
6. Query Languages Implementation
Structured Query Language (SQL) is a major query language used by users of database systems to extract, sort, and update their records in the database.
With SQL, users can access their information in a database without prerequisite programming language knowledge.
7. Access to Multiple Users
With the help of a Multi-User Access Database Management System, many other users can access the same information or data stored in a database.
However, there are limits to which a user can access records since an authorized user reserves the right to restrict anyone from altering or viewing specific information.
8. Retention of Data Integrity
Even though database systems are easily accessible to many database users, editing of existing data and manipulation can only be done by a single user simultaneously.
You can avoid data corruption, thus, retaining and maintaining the data integrity.
9. Metadata Catalog Management
Metadata is data that brings records of other data in the picture. It does not provide information about images or contents of the database.
The data dictionary and the metadata library feature in DBMS software shows the organization of the database and its other elements.
10. Data Durability
There is no risk of data loss in DBMS as data are stored permanently. In a situation where data is lost, recovery processes can be done, such as ARIES, to recover records before the data loss. Hence, your data is sure to be safe with DBMS.
Elements of a Database System
There are several elements o a database system.
1. Database Management System Languages
Users can use some key languages to interact with a database system.
Data Definition Language (DDL)
A database administrator uses this access language to analyze a database's internal, external, and logical schemas.
Data Manipulation Language (DML)
Database users can use Data Manipulation Language to recover, input, manipulate and scrap errors in a database.
The algorithm of this database level is contained in what is called General Purpose Programming Language and can also be supplied with a front-end querying object.
Structured Query Language (SQL)
SQL is a database access language used in relational databases. It performs the function of both DDL and DML. The language could be used as an interactive SQL and contained in a particular programming language, “embedded SQL.”
2. Users of Database
In a simple database, just a single user is authorized to update, delete, manipulate, retrieve or store data from the database. You can not share data with another user.
However, many users are involved in the utility, collation, storage, and recovery of the database in big organizations with more than hundreds of database users.
A database designer is saddled with the responsibility of deciding on data suitable for the database and selecting a suitable arrangement or structure for keeping a data record.
The database designer’s sole responsibility is designing a schema using a database access language known as a conceptual schema.
A database designer must carry out all activities before the database is activated for many end users to access. As part of his responsibility, the database designer must be conversant and acquainted with every single database user to be able to implement their desired designs.
Controlling and overseeing the database resources is the sheer responsibility of a Database Administrator. This individual oversees and monitors every activity on the database systems and decides which is used to access information on the database in real-world systems.
The database administrator also uses hardware and software utilities to aid his tasks. Unlike the database designer, that designs the conceptual schema, a database administrator designs the physical and external schema.
This individual observes the performance of the database system application programs using metrics like Key Performance Indicators (KPIs).
The algorithm, also known as a procedure, is the steps taken when performing an instruction or a task in a database management system. It takes charge of every operation on a database, such as storing, backups, access control, installation, and setup.
Hardware is the physical component of a database system that we can see and touch. It includes electronic devices like computer systems and storage devices like hard drives to launch the DBMS software and store considered data.
This database system element gives access to real-time users and facilitates interaction between users and the Database Programs.
Other hardware, such as keyboards, which are used to enter commands to the DBMS software, plus RAM and ROM, are all the major components of a database system hardware.
Software is an important element of a database system. It refers to programs that aid the management and control of the entire database, starting from the Operating System (OS), network software, and database software that helps share information and data.