Exploring Query Plan Scan Nodes with SQL EXPLAIN

QuestDB is an open-source time-series database designed for high-performance workloads, offering ultra-low latency, high ingestion throughput, and a multi-tier storage engine with native support for Parquet and SQL, which ensures data portability and AI readiness without vendor lock-in. The database employs various scan nodes to optimize SQL query performance, including Frame scans, Interval scans, and Index scans, each with distinct characteristics that influence how data is fetched and processed. Frame scans, also known as Full Table Scans, read all rows of a table, while Interval scans optimize queries with timestamp conditions by reducing the scan to specific intervals. Index scans differ by first accessing an index before retrieving relevant table rows, making them suitable for queries with indexed columns. QuestDB's EXPLAIN command provides insights into how queries are executed, allowing users to optimize their queries by understanding scan directions, scan boundaries, and the use of index keys. By learning to navigate these scan nodes and employing strategic query conditions, users can significantly enhance the efficiency of their SQL queries in QuestDB.