Cost Based Optimization
Cost Based Optimization (CBO) is a query optimization technique used in database management systems to determine the most efficient execution plan for a SQL query by estimating and comparing the 'cost' of different possible plans. It relies on statistical metadata about the data (e.g., table sizes, column distributions, indexes) to model resource usage such as CPU, I/O, and memory. The optimizer selects the plan with the lowest estimated cost to improve query performance and reduce execution time.
Developers should learn and use Cost Based Optimization when working with relational databases like PostgreSQL, Oracle, or MySQL to enhance query efficiency in data-intensive applications, such as analytics platforms, e-commerce systems, or large-scale web services. It is crucial for optimizing complex queries involving joins, subqueries, or aggregations, as it helps avoid performance bottlenecks and ensures scalable database operations by leveraging database statistics for informed decision-making.