As everyone knows, a database is a collection of information of various types, which we collectively call data. Database management systems or DBMS are designed to store and manage databases. DBMS is primarily a software system that uses standard methods and protocols to store and organize data. Data can be added, deleted, updated, or traversed with the use of various queries and algorithms used by database management systems. Further in this article, we will discuss different types of database management systems in practice.
Different types of database management systems
There are various types of DBMS systems. Here is a quick list:
- Hierarchical database management systems.
- Network database management systems.
- Relational database management systems (SQL DBs.)
- Object-oriented database management systems.
- ER model database management systems.
- Graph database management systems.
- NoSQL (non-relational) database management systems.
Apart from these, now there is a new generation of DBMS, too, as NewSQL database management systems, which claim to combine SQL and NoSQL database systems’ benefits.
Let us explore this one by one.
In these types of database management systems, data is stored primarily in a parent/child relationship model. The hierarchical DBMS, besides the actual data to be stored, the records also may contain information about their parent-child group relationships.
In this model, data is also stored in a tree structure. It means storage is made as a collection of fields where they contain a single value. Records may be linked to one another through links in the parent-child relationship. In the hierarchical DBMS model, each of the child records may have only one parent record. However, a parent can have multiple child records. In order to retrieve data, we have to traverse through each of the trees until the intended record is found.
Hierarchical databases can be easily accessed and quickly updated when needed. As this model has a tree structure and the relationships of the nodes between the records are well-defined, it can be easily managed. When it comes to the disadvantages of the hierarchical model and the types of database structure, each of the children in the tree may have only one parent. So, the linkage of relationships between children is not permitted even if it makes sense from a logical standpoint.
Network databases or network DBMS are used to create a different relationship between the database entities. These are mainly used for large database structures. Network databases are examples of hierarchical database models, but instead of the node having only a single parent, network nodes can have relationships with various entities.
So, a network database may look more like a cobweb than a tree structure. In the network databases, children are known as members, and parents are known as occupiers. The major difference between each child is that it can have more than a single parent. Otherwise, this network data model’s structure is more or less the same as that of a hierarchical data model. Data in the network database is well organized with a many-to-many relationship.
Relational database model
Also known as RDBMS, relational database management systems define the relationship between various data fields, which are stored in a table form, consisting of rows and columns. Each column of the database table represents a unique attribute, and each row in the table represents a record.
There are different fields in the table representing different values. SQL or structured query language is used to query the relational databases and retrieve information. SQL can perform various operations like insert, update, delete, and search for distinct records.
Relational DBMS work on each table, which has a unique key field. Key fields are used to connect one table of data to another one. Relational databases are now very widely used and so popular. Some of the most popular enterprise relational database management systems are SQL Server, Oracle SQL Lite, MySQL, and DB2 from IBM, etc.
The major advantages of relational databases are that it can be used instantly with minimal or no training. The database entries can also be modified without restructuring the entire body. In the case of RDBMS, we need to follow some properties as the values are atomic, each row is standalone, column values remain the same, the sequence of the row is insignificant, and each of the columns has a common name. For more information, contact RemoteDBA.com.
Object-oriented database model
The object-oriented model goes beyond the basic requirements of storage and retrieval of the database objects. An object-oriented system’s approach is more analogic of the applications and the development into a constant data model of language environment. Applications related to object-oriented models require less coding, and it introduces more natural data modeling and codebase, which is easy to maintain.
The major benefit of object-oriented DBMS is the ability to mix and match the objects, which can be easily reused and provide an incredible multimedia capacity. However, object-oriented databases are more expensive compared to other models.
Graph databases usually come under the NoSQL DBMS, which uses a graph structure to raise some queries. Data is stored in the form of notes and properties in graph databases. In any given graph database, nodes represent the entity like a person, customer, or object. Node is equal to a record as in the relational DBMS.
ER or Entity-Relationship Model databases
The ER model is implemented as a database too. In a simple relational DBMS implementation, each of the rows of given tables represents one instance or one entity type. Each field in the tables also represents an attribute type. In relational DBMS, relationships between different entities may be implemented by storing a primary key of one entity as a foreign key in the table of another. Peter Chin developed the entity-relationship model.
Document DB also comes with NoSQL databases. It stores data in document formats. Each of the documents represents data, its relationship between different data elements, and different attributes of data. Document databases store data in the key-value format. Document databases have become very popular now due to their NoSQL and storage properties.
So, there are various choices when it comes to choosing your enterprise database management system. Primarily, relational databases and non-relational databases are there, among which you can make further choices of the best matching DBMS system based on your requirements.