How do you enhance your database design with views, indexes, and triggers?

1 What are views?

A view is a virtual table that displays the result of a query, without storing the data physically. You can use views to simplify complex queries, hide sensitive data, and create reusable data sets. For example, you can create a view that shows the total sales and profit for each product category, based on multiple tables and calculations. To create a view, you use the CREATE VIEW statement, followed by the name of the view and the query that defines it. To query a view, you use the same syntax as querying a table.

2 What are indexes?

An index is a data structure that helps speed up the retrieval of data from a table. You can use indexes to improve the performance of queries that use filters, joins, or sorting. For example, you can create an index on the product name column, so that the database can quickly find the matching rows when you search for a specific product. To create an index, you use the CREATE INDEX statement, followed by the name of the index and the column or columns that you want to index. To delete an index, you use the DROP INDEX statement.

3 What are triggers?

A trigger is a stored procedure that executes automatically when a certain event occurs on a table or a view. You can use triggers to enforce business rules, audit data changes, or perform cascading actions. For example, you can create a trigger that updates the inventory level whenever a new order is inserted, deleted, or updated. To create a trigger, you use the CREATE TRIGGER statement, followed by the name of the trigger, the event that activates it, and the code that defines the action. To delete a trigger, you use the DROP TRIGGER statement.

4 How to use views, indexes, and triggers effectively?

Views, indexes, and triggers can be useful when designing a database, but they also have some drawbacks and limitations. To make sure you use them wisely, it's important to follow some best practices. For views, focus on simplifying queries and protecting data, but avoid nesting too many views or creating views that are not frequently used, as this can affect performance and maintenance. When it comes to indexes, they can speed up queries and sorting, however, too many indexes or indexing non-selective columns can increase storage space and update time. Finally, triggers are useful for implementing logic and consistency but complex or redundant triggers can cause errors and performance issues.

5 How to test and monitor your database design?

Once you create or modify your views, indexes, and triggers, you need to test and monitor their impact on your database. To do so, you can use EXPLAIN or EXPLAIN PLAN statements to analyze the execution plan and cost of your queries, and compare them before and after applying the changes. Performance monitoring tools or scripts can measure the response time, throughput, and resource utilization of your database, while error logging and debugging tools or techniques can track and resolve any errors or exceptions that occur in your views, indexes, or triggers. All of these methods can help identify any bottlenecks or anomalies in your system.

6 How to learn more about database design?

Database design is a vast and evolving topic, and there is always more to learn and improve. To deepen your knowledge and skills, you may want to explore online courses and tutorials on the fundamentals and advanced topics of database design, such as data modeling, normalization, denormalization, and optimization. Additionally, books and articles can provide in-depth explanations and examples of database design principles and practices. For tips, tricks, and insights from experts and peers in the field of database administration and design, you can look into blogs and forums.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?