If I have read-only tables in Postgres, should I index them heavily?

Indexing in Postgres is a technique to optimize database performance by creating copies of selected columns from a table, organized such that specific rows can be found quickly without scanning the entire table. For read-only tables, heavy indexing might seem beneficial as it does not affect write operations. However, factors like table size, query type, data format, and resource constraints should be considered when deciding on an indexing strategy. For small tables (up to a few thousand rows), full table scans can be as efficient or even faster than using an index. As the table size grows, indexes become more beneficial, especially for complex queries involving multiple conditions. High cardinality and easily orderable data types work best for indexing. Index maintenance and traversal consume CPU cycles, so it is essential to balance the benefits of indexing with its resource consumption. In conclusion, an effective indexing strategy in Postgres requires a careful consideration of these factors to optimize database performance.