Choosing the right Postgres indexes

Indexes in Postgres can significantly improve query performance by allowing for faster data retrieval, especially as table sizes grow. However, they come with a cost of extra disk space and slightly slower write operations. Therefore, it's important to add indexes only when necessary, such as for frequently run queries that filter out a high proportion of rows or require specific ordering. B-tree index is the default and most commonly used type of index in Postgres. Other types include GIN, GiST, hash, BRIN, and SP-GiST indexes, each with its own use cases. To identify when an index might be missing, tools like EXPLAIN ANALYZE, Query Insights, or performance dashboards can be used to monitor sequential scans on tables.