What do you look at in EXPLAIN when analyzing a query?

When analyzing EXPLAIN, I pay attention to several key points:

• Type of access to tables (Seq Scan, Index Scan, Bitmap Index Scan) — index scanning is usually faster than sequential.
• Order of table joins — it is important to process smaller data volumes first.
• Cost estimation — shows approximate costs of executing the operation, helping to identify bottlenecks.
• Number of rows — how many rows are expected to be processed at each step.
• Use of filters and conditions — how effectively WHERE and JOIN are applied.

I also look for the presence of sorts, hash joins, or merge joins to understand which algorithms the planner uses. This helps in making decisions about adding indexes or rewriting the query to improve performance.