When developing a database, it is essential that you carefully examine the approach towards agile database design from the outset to avoid any issues. As change will more than likely occur, it is essential that you develop a system that allows for change to happen as smoothly as possible.
To have a scalable application, it is vital that the database design is efficient as the data model and the database design will define the overall database structure, the relationships between the different data sets, and is part of the foundation on which the database application is built.
The Application Source Code
It needs to be noted that the application source code is not the same item as the database design. While both of these elements can act as blueprints for an item to be built, and they can change as time progresses, when a source code of the application alters, the entire application is changed.
The DevOps Database Solutions
The current instances are not only modified, but are created as a new element. On the other hand, database changes are applied directly to the instance. It is for this reason, that the application source code editing and maintenance methods are not appropriate for database design.
Similarly, while application source coding only deals with the final state in which it is found, the database design allows each individual change to be considered and noted. All chances to the database need to be recorded independently; thereby, they can be applied to other instances of the database with the final state of the database design being recorded in the overall database model.
Furthermore, the only reason changes should be made to a current database instance is via alteration of the specific SQL statements. Remember that changes cannot be implemented partially, meaning that they are either completed successfully or not at all. They should also be completed in a suitable sequence for repeatability purposes on behalf of dependences that exist between the alterations.
The Best Practices
It is a best practice for people who wish to make changes to the agile database design to first file a request. The requests are then recorded and will present an audit trail. Alterations must be reviewed and approved by the data modeller to ensure the design remains beneficial and scalable. The data modeller is also responsible for any updating of the database model, which is a record of the full database design; thereby, producing the SQL statement implementing change.
The role of the database modeller can be done via automation, causing the role of a database modeller or database designer to be a full-time position during the initial stage of development exclusively. You can use a database diagram tool to map things
While the development cycles of the database involve a database designer, the positive can be filled by another individual within the development cycle, such as a database administrator or developer, as it is no longer as tiresome or time-consuming.
All databases and database change is provided with a unique identifier that identifies particular changes. The identifier does not take note of the database instances to which it is applied or the versions of the application.
All modifications to a database instance need to be recorded in the database instance itself to avoid any application of the same change twice or more. This means you should maintain some form of change history spreadsheet within the database instance; thereby, including the time and date for each change and what occurred.
All sets of changes must be stored in a single change log book including the change identifier number, as well as the SQL statement used to implement the change and allow all necessary alterations to be sequenced and located. The change log needs to be well-structured so a program can read and decode the modifications listed in it. However, there should be separate instances of the database design, and the change log file in all versions of the application source code should be made so changes can be logged independently.
The Database Changes
SQL statements are typically associated with a single database product, such as MySQL, SQL Server, Sybase or Oracle. The change log will record the individual SQL statements for each of the supported database products and each individual database change. This means that all changes made will have a unique identifier and SQL statements for the database product which is clearly labelled using the database product name.
The whole solution is created in a program and is run during an application upgrade. It opens the change log XML file reading in each individual change. If the change has not yet been applied to a further database instance, then the corresponding SQL statement is executed and recorded into the change history metadata table.
The significance of a well-formed agile database design cannot be undermined. While there are various best practices for database developers, there are certain tips that I have found beneficial. I feel that if you utilize these tips, you can ensure a scalable database application that will run and operate smoothly.