The different phases of the database development life cycle (DDLC) in the Database Management System (DBMS) are explained below −
- Requirement analysis.
- Database design.
- Evaluation and selection.
- Logical database design.
- Physical database design.
- Data loading.
- Testing and performance tuning.
Now, let us understand these phases one by one.
The most important step in implementing a database system is to find out what is needed, i.e., what type of database is required for the business organization, the daily volume of data, how much data needs to be stored in the master files, etc.
To collect all this information, a database analyst spends a lot of time within the business organization talking to end users and getting acquainted with the day-to-day process.
In this phase, the database designers will decide on the database model that perfectly suits the organization’s requirements. The database designers will study the documents prepared by the analysis in the requirement analysis stage and then start the development of a system model that fulfills the needs.
Evaluation And Selection
In this phase, we evaluate the diverse database management systems and choose the one that perfectly suits the organization’s requirements.
To identify the best performing database, end users should be involved.
Logical Database Design
Once the evaluation and selection phase is completed successfully, the next step is logical database design.
This design is translated into an internal model, which includes mapping of all objects, i.e., design of tables, indexes, views, transactions, access privileges, etc.,
Physical Database Design
This phase selects and characterizes the database’s data storage and data access.
The data storage depends on the type of devices supported by the hardware and the data access methods.
Physical design is very vital because bad design results in poor performance.
Database implementation needs the formation of special storage-related constructs.
These constructs consist of storage groups, tablespaces, data files, tables, etc.
Once the database has been created, the data must be loaded into the database.
The data must be converted if the loaded date is in a different format.
The end users and application programs access the database in this phase.
This stage includes adding new data, modifying existing data, and deleting unlimited data.
This phase provides useful information and helps management to make a business decision.
It is one of the ongoing phases in DDLC.
The major tasks included are database backup and recovery, access management, hardware maintenance, etc.